Econstudentlog

A few more physics lectures

I’ve spent most of the day watching videos like these (I’ve now seen the first 12 lectures). He rambles a bit sometimes, but it’s youtube – it’s easy to skip stuff if you don’t want to watch him spend several minutes talking about his hybrid car and how awesome it is (or whatever). Unless you’re a physics major – in which case you’re not in the target group anyway – I’d be willing to bet there’s stuff covered in these lectures you didn’t know. Stuff you didn’t know you didn’t know, because you didn’t think about it.

June 30, 2012 Posted by | Lectures, Physics | Leave a comment

Some physics lectures and a bit of other stuff

i. A few physics lectures from Berkeley’s youtube channel. As they put it in the description: “The most interesting and important topics in physics, stressing conceptual understanding rather than math, with applications to current events.” I think it’s awesome that stuff like this is available for free for you to watch whenever you want to:

Note that there are a lot of lectures available here (26, each lasting about ~70 minutes).

ii. I may have blogged this before, but I don’t think so. Anyway this is just so cute you’ll not be harmed by watching it again in case you already have:

iii. “There’s also a long history of seemingly rational scientists who were willing to sacrifice their physical comfort, as well as their lives, for the sake of knowledge.” Keyword: Seemingly.

I won’t comment on the others, but mr. Hill’s experiment as described in that article could in my opinion aptly be categorized as insane (‘do the same thing over and over and expect different results…’).

iv. “before the development of modern prison systems, the death penalty was also used as a generalised form of punishment. During the reign of Henry VIII, as many as 72,000 people are estimated to have been executed.[26] By 1820 in Britain, there were 160 crimes that were punishable by death, including crimes such as shoplifting, petty theft, stealing cattle, or cutting down trees in public place.” (more)

June 29, 2012 Posted by | biology, Lectures, Physics | Leave a comment

South Asia: From early villages to buddhism

I mentioned the chapter in a previous post, but I didn’t cover it in any detail and I thought that I probably should, even if it’s not – in my opinion – one of the better chapters in the book. I’m currently finishing the chapter after that one, chapter 15, about ‘Complex Societies of East and Southeast Asia’, which covers stuff taking place in that region during the time period from the 3rd century BC up to the end of the Khmer Empire.

Having some background knowledge about the stuff that’s covered in a specific chapter, a situation I’ve been in a few times, can truly impact reading experience, and I’m not sure I’d have read the book quite the same way if I’d read it some years ago. Generally, if you know stuff from other sources it’s easier to realize just how much stuff is actually covered in a book like this. Robin Lane Fox used more than 700 pages in his book The Classical World to cover what The Human Past spends, what, 4-5 pages on? Similarly, Gernet spends more than 100 pages on the developments taking place from the early Warring States period of Ancient China to the end of the Han Dynasty – a much more condensed version is naturally presented in THP. Heather’s book? Well, here’s what THP has to say about one of the main subjects covered in that book, THP page 429:

“In eastern Europe, the River Danube formed the frontier of the empire. Over the centuries that followed, extensive interaction took place between the Roman provinces and the territories beyond, in the form of trade, cultural and technological borrowing, diplomatic exchange, and military action, until the Roman/non-Roman division dissolved in the late 4th and 5th centuries AD.”

That’s one way of putting it. Or you could write a book about it. Or several books, many have been written about that topic. Something I have thought of as rather interesting is how the book is actually, the scope of the material covered taken into consideration, quite focused on the evidence and the specifics – main sites, findings, etc. There’s less room to spare for ‘the big picture’ than you might have thought, even if it is fundamentally pretty much nothing but a book about big picture stuff. But a lot of the big picture stuff that is included is big picture stuff that has been made plausible by presenting or at least talking about some the evidence first – you don’t see many conclusions you don’t know how the authors arrived at. ‘After having looked closely at the middens found (you’d be surprised how much you can learn from old middens) at these three sites, we can see that the number of sheep bone fragments increase over time and that the number of gazelle bone fragments decrease over time, indicating that (something about domestication and decreased reliance on game as a protein source)’ – no, that’s not a quote from the book, but most of the book is conceptually like this: What did the people living at that point in time leave behind, and what can we conclude based on what they left behind? It’s fascinating how much stuff can actually be covered in such a manner in such a short amount of space, all things taken into consideration.

I expect to have another one of those ‘I’ve read about this before’-experiences when I read chapter 17 (From Village to Empire in South America), given that I’ve previously read Metraux. It should be mentioned that having read other stuff about a subject also makes the newly acquired knowledge easier to put into context and recall afterwards but you guys probably already know that. It’s great if the authors disagree about something, because then you start to feel a need to remember what the other guy said, leading to a more critical reading of both materials. The fact that I hadn’t read anything about the prehistory of South Asia before may be part of why I didn’t much like the chapter, but it’s not the only reason. Anyway, with all that out of the way; I’ve added some links to the type of stuff that’s covered in chapter 14 below. I’ve tried to select only somewhat-substantial articles:

Mehrgarh
Indus Valley Civilization
Cemetery H culture
Indus script
Anuradhapura
Mohenjo-daro
Mahajanapadas
Mauryan Empire
Kushan empire

Western Satraps
Sunga Dynasty (/Empire)
Ashoka

June 28, 2012 Posted by | anthropology, archaeology, books | Leave a comment

The Classical World (#?)

As mentioned on the twitter, I’ve been finishing Robin Lane Fox’ The Classical World today. Though I did read far most of the book a few years ago, I actually never completely finished it; I’m pretty sure my non-completion of the book was for reasons related to ‘work’/’exams’ as the book is certainly far from boring, even if it is a bit ‘dense’ here and there. Well, it’s actually not completely true that I didn’t finish it – I did technically ‘read’ it all the way through, but I didn’t study the last part of the book. The painting of the pages and the note-taking in the margins stopped a few hundred pages from the finish line because I just wanted to get it over with as soon as possible for reasons having nothing to do with the quality of the book. I’ve felt bad about this recently, particularly as I was reading Heather.

For the same reasons I didn’t finish the book completely, I did not blog the book in very much detail the first time around; a few general remarks and some quotes from the first 150 pages seems to be all I’ve posted so far. As I started reading today, I decided that it probably couldn’t hurt to write at last one other post on the book here – it seemed a little bit wrong to me that a book like this got much less coverage here than does a fiction book you can read in a few hours. I think the book is on average roughly in my ~25 pages/hour-category, which is not quite as ‘bad’ as a standard textbook, but certainly a much more demanding read than a random novel (..25/page is for intensive reading/studying; including necessary breaks and so on means that the actual time expenditure is somewhat higher. On the other hand, if you just ‘read’ it without worrying too much about what will stick – the way I dealt with the last part when I first read it – you can probably do it quite a bit faster).

It takes a lot of time to write posts like these, and if not for the fact that they help me remember stuff I probably wouldn’t write them – so I won’t promise here to also cover the rest of the book, even though it is my intent right now to write at least one more post about the book (I haven’t covered anything of what I’ve read today in the post below). Perhaps needless to say, there’s a lot more than one post left in the book.

I must say before going any further that it was a great help for me, in terms of getting a better understanding of the material covered at the end of the book, to have quite recently read chapters 12 and 13 in The Human Past as well as Heather (another book I may also have to get back to at one point..).

All that out of the way, some quotes:

i. “When a husband and wife are at odds with one another, they are much more likely to be reconciled for the sake of their children than to detest the children they have had together because of the wrongs they have done to one another.” Demostenes, speech against Boetus, 39.23 (348 BC)”

ii. “In Athenian citizen-households, the father decided if a new-born child was to live: he would run round the hearth carrying it on the fifth day of its life, in a ceremony called the Amphidromia. On the tenth day the child would usually be named. Aristotle remarks that parents waited for ten days because so many children died meanwhile.”

iii. “all young girls of citizen-birth (probably) engaged for a while in a splendid rite of transition known as the arkteia. Between the ages of five and ten, they would play at being ‘bears’, possibly to symbolize their wild immature nature, which was to be tamed in due course by men and marriage. […] Four or five years after playing at ‘bears’ [i.e. at the age of 9-15… – US] Athenian girls would be married. Girls were not formally educated in schools (in the classical period, at least) and any reading which they picked up would be learned in a household, from mothers (perhaps) or, in richer households, from literate slaves: girls might go to each other’s houses for the sake of it. Boys, however, would be educated, usually beginning at seven and going on at least to fourteen; their teaching included writing, reading (including the reading of poets) and music and athletics. […] In due course, young men would marry, but marriage for men tends to be recommended at quite a late age, between twenty-five and thirty. Until then, young men could satisfy their hormones by using slave prostitutes […] They could try slave-girls in their father’s households, or a more permanent slave-courtesan (or a share in one); they also had one another.”

[incidentally, Lane Fox’ evaluation of the evidence does not match this wikipedia article. According to the article, the hetairai were “Mostly ex-slaves from other cities” – according to Fox, “hetairai were usually slaves.”]

iv. “Notoriously, he [Aristotle] had views on slaves and women. Unnamed thinkers, probably in Socrates’ Athens, had denied that slavery was ‘in accordance with nature’; Aristotle disagreed. There were ‘slaves by nature’, he believed, who were incapable of foresight, deliberation or practical wisdom. At times he even writes as if they are animals. Most of the slaves whom Aristotle saw in Athens, western Asia or Macedon would have been non-Greek ‘barbarians’, whom he regarded as inferior by nature: he says explicitly that the existence of natural slaves can be proved both by theory and by experience.6 His views about natural slavery caused his own arguments serious problems on many counts, but they were not just a passing consequence of his theories on ruling or the household. What he saw in his own experience seemed to require them, just as his perceptions of women accounted for his view that they are defective versions of the rational ‘polis-male’: what he saw were uneducated, irrational beings, who would typically lament in public. Although women have a trace of a power of reason, it is very feeble and ‘without authority’.7 For barbarians and women, therefore, freedom is a wholly inappropriate state. […]

He has some role, surely, in the continuing curiosity of Alexander about the Asia which he was conquering, but his main role appears to be in passing on his awful sense of geography. Aristotle believed that the edge of the world was visible from what we call the Hindu Kush mountains in Afghanistan: like many, Aristotle confused them with the distant Caucasus. He also reasoned that the river Indus ran neatly around to Egypt and that modern Morocco is quite close to India, on the grounds that both lands have elephants. This view of the world can only have strengthened the young Alexander’s resolve to conquer to the edge of it.”

v. “The fourth-century democracy was not at all in retreat, until the Macedonians ended it forcibly in 322 BC. […] In the end, the people of Attica were still the only sovereign body, meeting in their assembly in the belief that ‘the people can do whatever seems good to it’. […] There was no ‘government’, no continuing group who ‘ran’ the place: the councillors still changed yearly, and their ‘recommendations’ had to be voted in by all the people. Since the death of Pericles a division had already become apparent between the military generals and the most prominent political orators. In the fourth century this division becomes even clearer, as does the Athenians’ propensity to prosecute generals who failed them on expeditions abroad. The people were highly suspicious of malpractice, and so their generals realized that they were well advised to work with a political orator who would champion them at home.
These political orators owed their pre-eminence to speaking and persuading. […] But without good speaking and a record of successful persuasion, an orator was soon a nobody. There was no new expertise, no specialized technology which only ‘those in politics’ had mastered. they sometimes had more information, but above all, they were the ones who spoke with success.”

vi. “painted pottery was of marginal importance to the Athenian economy. What mattered, above all, was the mining of silver and the export of olive oil.”

vii. “As a general, Alexander remained globally famous, but his conquests were essentially won with the army which Philip had created.”

viii. “By 302 [approximately 20 years after the death of Alexander the Great] there were five competing kings, but a year later they were reduced to four when Seleucus defeated the elderly Antigonus and killed him. India had by now been given away, but the rest of Alexander’s territories stayed under Greek rule. In 281 BC, after more years of struggle, the four kings became three when Seleucus, an Alexander-survivor, killed off Lysimachus, one of Alexander’s bodyguards, at an old site of Persian settlement, ‘Cyrus Plain’, in western Asia. From 281 BC until the clashes with Rome, Alexander’s Greek world remained split into the resulting three kingdoms: the Seleucid kings in Asia (without India), the Ptolemies in Egypt and the Antigonids in Macedon, bound by garrisons and treaties to the city-states and ‘leagues’ in Greece.”

ix. “Seatransport was relatively quick and ever cheaper in bulk as the cargoes of merchant-ships increased up to 500 tons by the Roman period. But it remained cheaper to transport heavy goods in bulk from one end of the Mediterranean to the other than to haul them without a river-way for seventy miles inland.”

x. “Into Egypt, the Macedonian rulers introduced tax-farming, whereby the collection of a particular tax was bid for in advance by contractors. The successful bidder had guaranteed to pay the sum he bid, but was free to collect more (or less) as he could. The system suited rulers who needed an assured revenue from taxes which had an unpredictable yearly yield.
Such taxes were very common in Hellenistic Egypt because the Ptolemies raised revenues by a multiplicity of individual charges, applied to particular types of asset and transaction. There was a salt tax on each adult man or woman, an oil tax, a tax nitron-soda (essential for cleaning clothes) and dozens of others.”

xi. “For a century or so, from 460 to 360 BC, there were fewer than ten years in all when the Romans were not at war.”

xii. “As in the Greek world, half of the city of Rome, the women, could not vote or hold political office. Unlike Athenian women, they were not even able to be priestesses of the gods, unless they were one of the six Vestal virgins. While their father or grandfather lived women were legally (like sons) in his ‘power’, and when he died they were put promptly (unlike sons) under the guardianship of their male next of kin. As perhaps more than half of Roman women aged twenty did not have fathers or grandfathers still alive (on a likely average), most adult women would be under guardianship. When they married, the predominant form of marriage conveyed them like children into the ‘hand’ of their husband.”

xiii. “the Senate could not legislate. It could pass advisory decisions (consulta) and for a while it either did or could vet any decision which was to go to an assembly and be made into a law. But the senators were not ‘the government’ nor was public business consigned for a matter of years to any representative body of delegates or magistrates, chosen from their number. As the Romans had not adopted a constitution from a lawgiver, it is we who look for their ‘constitution’ in what was a bundle of evolving customs, traditions and precedents. At the heart of their practise, ther was a two-headed beast, as some of them later characterized it: the venerable senators and the (formally) sovereign plebs.” [see also this and this]

xiv. “As in Athens, there was never a Roman ‘golden age’ before slavery. Slave-owning was not, then, seen as unbridled luxury; rather, ‘luxury’ was ascribed to rival cities in Italy, south of slave-owning Rome, where it was cited as their undoing.”

June 25, 2012 Posted by | anthropology, books, history | 2 Comments

Science does more harm than good?

I just had to share this (US data, from the GSS):

Razib doesn’t comment, he just gives you the data. I won’t comment much on the above graph now either, but that’s only because I’m dumbstruck right now – I have just no idea what to even say to all those people who do not strongly disagree.

June 23, 2012 Posted by | data, science | 3 Comments

Stuff

i. From The future of infectious diseases. Watch it.:

“Take home messages:

  • You can watch evolution in progress in quickly-reproducing organisms, like malaria
  • Over 100,000 Americans die of infections that were easily treated 30 years ago due to the evolution of resistance (twice the number of people who will die in car crashes).
  • In an arms race between us and infectious diseases, we lose.
  • We need to understand the evolutionary forces unleashed by medicine before we can manage infectious disease
  • We need to ask, “Will (this drug) STAY safe, and CONTINUE to work”, not just if it is safe and whether it will work.
  • The Lancet (a high impact medical journal) rejected an evolutionary paper addressing malaria because, “a good understanding of evolutionary biology is beyond most of our readers.””

Point 3 is one I try to remember to bring up every time I find myself in a discussion about matters related to how the future development of medicine will look like. Unless you do not agree with that one, it’s very hard to be an optimist about the future of medicine.

ii. I discussed this subject briefly yesterday, and I later started thinking about whether I’d actually blogged this (pdf) publication (in Danish, sorry), PISA København 2010, which deals with the educational achievements of Danish children in Copenhagen who left the 9th grade in 2010. I don’t think I have (I couldn’t find anything in the archives), so I decided to add a link here as well as a few observations from the paper:

“Opdeles eleverne efter andelen af indvandrerelever på deres skoles niende klassetrin, finder man generelt, at jo større andel af indvandrere, des lavere gennemsnitlig læsetestscore.” (a (loose) translation: ‘If the students are distributed according to the proportion of immigrant-pupils in the 9th grade, a general finding is that the larger the share of immigrants, the lower the average reading test score’).

Immigrant groups perform worse than non-immigrant groups, and the proportion of immigrants also affects the performance of the non-immgrant pupils (negatively) for some, though not all, specifications. The ‘Danish’ pupils enrolled in schools where the proportion of immigrant pupils exceeds 50% do significantly worse than do Danish pupils who are enrolled in schools where the immigrant pupil proportion is below 25% (p.11). Immigrant pupils also do better in schools with less than 25% immigrants than they do in schools where the proportion of immigrant pupils exceeds that number (p.11).

A table from the report (p.31), click to view full size:

The above table contains some numbers related to PISA’s reading test, with a special focus on the proportion of pupils in the sample who are functionally illiterate, corresponding to a reading performance of less than level 2 on the PISA scale (which is described in more details in the Appendix, p. 82-83 – I will not go into details here unless asked). In 2010, 14% of ‘Danish’ pupils and 42% of ‘immigrant pupils’ from schools in Copenhagen were functionally illiterate judging from the PISA reading test. There’s a big gender gap – 17% of the girls and 30% of the boys were functionally illiterate. The difference between the performances of first (44%) and second (41%) generation immigrant pupils is not statistically significant. Almost half of all 9th grade immigrant pupils in the public school system – 48% of first generation immigrant pupils in public schools and 46% of second generation immigrant pupils in public schools – were functionally illiterate.

There’s a lot of hidden variation in the immigrant numbers and not all immigrant groups do equally badly. It’s worth having in mind that these results are actually averages. Taking not-insignificant heterogeneity in the immigrant sample into account, it’s surely the case that some immigrant groups do even worse than these numbers might imply. If you look at the school level, some of the numbers probably get much worse. The Rockwool Foundation found in 2007 that 64% of pupils of Arab origin in the 9th grade were functionally illiterate (Danish link). In the PISA report they don’t go into much details, but they do note that pupils of Lebanese (/Palestinians), Iraqi and Turkish origin do worse than do pupils of Pakistani origin (also from p. 11).

iii. Another paper, Moral Hypocrisy, Power and Social Preferences, by Rustichini and Villeval (via Robin Hanson):

“Abstract: We show with a laboratory experiment that individuals adjust their moral principles to the situation and to their actions, just as much as they adjust their actions to their principles. We first elicit the individuals’ principles regarding the fairness and unfairness of allocations in three different scenarios (a Dictator game, an Ultimatum game, and a Trust game). One week later, the same individuals are invited to play those same games with monetary compensation. Finally in the same session we elicit again their principles regarding the fairness and unfairness of allocations in the same three scenarios.

Our results show that individuals adjust abstract norms to fit the game, their role and the choices they made. First, norms that appear abstract and universal take into account the bargaining power of the two sides. The strong side bends the norm in its favor and the weak side agrees: Stated fairness is a compromise with power. Second, in most situations, individuals adjust the range of fair shares after playing the game for real money compared with their initial statement. Third, the discrepancy between hypothetical and real behavior is larger in games where real choices have no strategic consequence (Dictator game and second mover in Trust game) than in those where they do (Ultimatum game). Finally the adjustment of principles to actions is mainly the fact of individuals who behave more selfishly and who have a stronger bargaining power.
The moral hypocrisy displayed (measured by the discrepancy between statements and actions chosen followed by an adjustment of principles to actions) appears produced by the attempt, not necessarily conscious, to strike a balance between self-image and immediate convenience.”

iv. False-Positive Psychology: Undisclosed Flexibility in Data Collection and Analysis Allows Presenting Anything as Significant, by Simmons, Nelson and Simonsohn. A pretty neat paper:

“Abstract
In this article, we accomplish two things. First, we show that despite empirical psychologists’ nominal endorsement of a low rate of false-positive findings (! .05), flexibility in data collection, analysis, and reporting dramatically increases actual false-positive rates. In many cases, a researcher is more likely to falsely find evidence that an effect exists than to correctly find evidence that it does not. We present computer simulations and a pair of actual experiments that demonstrate how unacceptably easy it is to accumulate (and report) statistically significant evidence for a false hypothesis. Second, we suggest a simple, low-cost, and straightforwardly effective disclosure-based solution to this problem. The solution involves six concrete requirements for authors and four guidelines for reviewers, all of which impose a minimal burden on the publication process.”

v. Cognitive Sophistication Does Not Attenuate the Bias Blind Spot, by West, Meserve & Stanovich:

“The so-called bias blind spot arises when people report that thinking biases are more prevalent in others than in themselves. Bias turns out to be relatively easy to recognize in the behaviors of others, but often difficult to detect in one’s own judgments. Most previous research on the bias blind spot has focused on bias in the social domain. In 2 studies, we found replicable bias blind spots with respect to many of the classic cognitive biases studied in the heuristics and biases literature (e.g., Tversky & Kahneman, 1974). Further, we found that none of these bias blind spots were attenuated by measures of cognitive sophistication such as cognitive ability or thinking dispositions related to bias. If anything, a larger bias blind spot was associated with higher cognitive ability. Additional analyses indicated that being free of the bias blind spot does not help a person avoid the actual classic cognitive biases. We discuss these findings in terms of a generic dual-process theory of cognition.”

I’ll just repeat part of that abstract: “none of these bias blind spots were attenuated by measures of cognitive sophistication such as cognitive ability or thinking dispositions related to bias. If anything, a larger bias blind spot was associated with higher cognitive ability.

A few other remarks from the paper (but do read all of it if you find the result interesting):

“the bias blind spot joins a small group of other effects such as myside bias and noncausal base-rate neglect (Stanovich & West, 2008b; Toplak & Stanovich, 2003) in being unmitigated by increases in intelligence. That cognitive sophistication does not mitigate the bias blind spot is consistent with the idea that the mechanisms that cause the bias are quite fundamental and not easily controlled strategically — that they reflect what is termed Type 1 processing in dual-process theory (Evans, 2008; Evans & Stanovich, in press). Two of the theoretical explanations of the effect considered by Pronin (2007)—naive realism and defaulting to introspection—posit the bias as emanating from cognitive mechanisms that are evolutionarily and computationally basic. Much research on the bias blind spot describes the asymmetry in bias detection in self compared to others as being spawned by a belief in naive realism—the idea that one’s perception of the world is objective and thus would be mirrored by others who are open-minded and unbiased in their views (Griffin & Ross, 1991; Pronin et al., 2002; Ross & Ward, 1996). Naive realism is developmentally primitive (Forguson & Gopnik, 1988; Gabennesch, 1990) and thus likely to be ubiquitous and operative in much of our basic information processing.

[rereading this, it reminded me of this quote, from a recent lesswrong article: “if you aren’t treating humans more like animals than most people are, then you’re modeling humans poorly. You are not an agenty homunculus “corrupted” by heuristics and biases. You just are heuristics and biases. And you respond to reinforcement, because most of your motivation systems still work like the motivation systems of other animals.”]

It is likewise with self-assessment based on introspective information, rather than behavioral information (Pronin & Kugler, 2007). The bias blind spot arises, on this view, because we rely on behavioral information for evaluations of others, but on introspection for evaluations of ourselves. The biases of others are easily detected in their overt behaviors, but when we introspect we will largely fail to detect the unconscious processes that are the sources of our own biases (Ehrlinger et al., 2005; Kahneman, 2011; Pronin et al., 2004; Wilson, 2002). When we fail to detect evidence of bias, we are apt to decide no bias has occurred and that our decision-making process was indeed objective and reasonable. This asymmetry in bias assessment information has as its source a ubiquitous and pervasive processing tendency— introspective reliance — that again is developmentally basic (Dennett, 1991; Sterelny, 2003).”

vi. Via Gwern, a meta-analysis on depression and exercise. There seems to be a short-term positive effect, but “there is little evidence of a long-term beneficial effect of exercise in patients with clinical depression.”

June 22, 2012 Posted by | data, demographics, education, papers, Psychology | 2 Comments

Quotes

i. “Diffused knowledge immortalizes itself.” (James Mackintosh)

ii. “In philosophy equally as in poetry it is the highest and most useful prerogative of genius to produce the strongest impressions of novelty, while it rescues admitted truths from the neglect caused by the very circumstance of their universal admission.” (Samuel Taylor Coleridge)

iii. “If I belong to any tradition, then it is the tradition which makes the masterpiece tell the performer what he should do; and not the performer telling the piece what it should be like, or the composer what he ought to have composed.” (Alfred Brendel)

iv. “People exaggerate both happiness and unhappiness; we are never so fortunate nor so unfortunate as people say we are.” (Honoré de Balzac)

v. “If you are to judge a man, you must know his secret thoughts, sorrows, and feelings; to know merely the outward events of a man’s life would only serve to make a chronological table — a fool’s notion of history.” (-ll-)

vi. “Study lends a kind of enchantment to all our surroundings. (L’étude prête une sorte de magie à tout ce qui nous environne.)” (-ll-)

vii. “One of the greatest pains to human nature is the pain of a new idea.” (Walter Bagehot)

viii. “You may talk of the tyranny of Nero and Tiberius; but the real tyranny is the tyranny of your next-door neighbor… Public opinion is a permeating influence, and it exacts obedience to itself; it requires us to think other men’s thoughts, to speak other men’s words, to follow other men’s habits.” (-ll-)

ix. “It is good to be without vices, but it is not good to be without temptations.” (-ll-)

x. “There are all kinds of interesting questions that come from a knowledge of science, which only adds to the excitement and mystery and awe of a flower. It only adds. I don’t understand how it subtracts. ” (Richard Feynman)

xi. “Don’t you believe in flying saucers, they ask me? Don’t you believe in telepathy? — in ancient astronauts? — in the Bermuda triangle? — in life after death?
No, I reply. No, no, no, no, and again no.
One person recently, goaded into desperation by the litany of unrelieved negation, burst out “Don’t you believe in anything?”
“Yes”, I said. “I believe in evidence. I believe in observation, measurement, and reasoning, confirmed by independent observers. I’ll believe anything, no matter how wild and ridiculous, if there is evidence for it. The wilder and more ridiculous something is, however, the firmer and more solid the evidence will have to be.”” (Isaac Asimov)

xii. “Happiness isn’t something you experience; it’s something you remember.” (Oscar Levant)

xiii. “My conscience is clear. I was simply doing my duty…” (Franz Stangl, SS-Hauptsturmführer and commandant of the Sobibor and Treblinka extermination camps)

xiv. “Every way of classifying a thing is but a way of handling it for some particular purpose.” (William James)

xv. “Nothing is so fatiguing as the eternal hanging on of an uncompleted task.” (-ll-)

xvi. “The way our group or class does things tends to determine the proper objects of attention, and thus prescribe the directions and limits of observation and memory. What is strange and foreign (that is to say outside the activities of the group) tends to be morally forbidden and intellectually suspect. It seems almost incredible to us, for example, that things which we know very well, could have escaped recognition in past ages. We incline to account for it by attributing congenital stupidity to our forerunners and by assuming superior native intelligence on our own part. But the explanation is that their modes of life did not call for attention to such facts, but held their minds riveted to other things.” (John Dewey)

xvii. “Every thinker puts some portion of an apparently stable world in peril and no one can wholly predict what will emerge in its place.” (-ll-)

xviii. “”Knowledge,” in the sense of information, means the working capital, the indispensable resources, of further inquiry; of finding out, or learning, more things. Frequently it is treated as an end in itself, and then the goal becomes to heap it up and display it when called for. This static, cold-storage ideal of knowledge is inimical to educative development. It not only lets occasions for thinking go unused, but it swamps thinking. No one could construct a house on ground cluttered with miscellaneous junk. Pupils who have stored their “minds” with all kinds of material which they have never put to intellectual uses are sure to be hampered when they try to think. They have no practice in selecting what is appropriate, and no criterion to go by; everything is on the same dead static level.” (-ll-)

xix. “The imagination is the medium of appreciation in every field. The engagement of the imagination is the only thing that makes any activity more than mechanical. Unfortunately, it is too customary to identify the imaginative with the imaginary, rather than with a warm and intimate taking in of the full scope of a situation.” (-ll-)

June 21, 2012 Posted by | quotes/aphorisms | Leave a comment

‘The Mediterranean World’ and ‘South Asia: From Early Villages to Buddhism’

The post title refers to the titles of the chapters 13 and 14 in The Human Past. I read the first chapter earlier today and expect to finish chapter 14 later this evening (though I’m now starting to think that may be a bit optimistic). They are both 40+ pages long, so there’s a lot of stuff covered here. Given that each chapter here corresponds to at least half a book in many other contexts, I figured I might as well blog my reading of this stuff more regularly than I’ve done so far. I’ve added some links to stuff covered in chapter 13, the one about the Mediterranean World – the time period covered is roughly the period from early 3rd millenium BC to the fall of the Roman Empire. I haven’t read all the articles so I can’t say if they agree with the book, but I’ll assume for now that many of the same themes are covered. It’s not unlikely that I may have linked to one or two of these before in my wikipedia articles posts, as this is (generally) stuff I’ve read about before, on more than one occasion (some of this stuff was part of the high school curriculum):

Minoan civilization.
Cycladic civilization.
Troy VII
Linear B
Mycenaean Greece
Greek Dark Ages
Polis
Phoenicia
Etruscan civilization
Olympia
Philip II of Macedon
Alexander the Great
Ptolemaic Kingdom
Punic Wars
Forum of Trajan
Pompeii
First Jewish–Roman War

June 20, 2012 Posted by | anthropology, archaeology, books, history | Leave a comment

Feet of clay

Read it today – good stuff. Some quotes from the book:

i.”‘A dwarf who can’t get the hang of metal? That must be unique.’
‘Pretty rare, sir. But I was quite good at alchemy.’
‘Guild member?’
‘Not any more, sir.’
‘Oh? How did you leave the guild?’
‘Through the roof, sir. But I’m pretty certain I know what I did wrong.’
Vimes leaned back. ‘The alchemists are always blowing things up. I never heard of them getting sacked for it.’
‘That’s because no one’s ever blown up the Guild Council, sir.’
‘What, all of it?’
‘Most of it, sir. All the easily detachable bits, at least.'”

ii. “‘It beats me why Ankh-Morpork wants to celebrate the fact it had a civil war three hundred years ago,’ said Angua, coming back to the here-and-now.
‘Why not? We won,’ said Carrot.
‘Yes, but you lost, too.'”

iii. “‘I think I’ll write it in my notebook, if you don’t mind,’ said Vimes.
‘Oh, well, if you prefer, I can recognize handwriting,’ said the imp proudly. ‘I’m quite advanced.’
Vimes pulled out his notebook and held it up. ‘Like this, he said?’
The imp squinted for a moment. ‘Yep,’ it said. ‘That’s handwriting, sure enough. Curly bits, spiky bits, all joined together. Yep. Handwriting. I’d recognize it anywhere.’
‘Aren’t you supposed to tell me what it says?’
The imp looked wary. ‘Says?’ it said. ‘It’s supposed to make noises?'”

iv. “It’s a pervasive and beguiling myth that the people who design instruments of death end up being killed by them. There is almost no foundation in fact. Colonel Shrapnel wasn’t blown up, M. Guillotin died with his head on, Colonel Gatling wasn’t shot. If it hadn’t been for the murder of cosh and blackjack maker Sir William Blunt-Instrument in an alleyway, the rumour would never have got started.”

v. “‘I reckon he’s been poisoned, Fred, and that’s the truth of it.’
Colon looked horrified. ‘Ye gods! Do you want me to get a doctor?’
‘Are you mad? We want him to live!'”

vi. “‘I want you to go back to the Watch House and take care of things.’
‘What things?’
‘Everything! Rise to the occasion. Move paper around. There’s that new shift rota to draw up. Shout at people! Read reports!’
Carrot saluted. ‘Yes, Commander Vimes.'”

vii. “Cheery looked around again. By now, if it had been a dwarf bar, the floor would be sticky with beer, the air would be full of flying quaff, and people would be singing. They’d probably be singing the latest dwarf tune, Gold, Gold, Gold, or one of the old favourites, like Gold, Gold, Gold, or the all-time biggie, Gold, Gold, Gold. In a few minutes, the first axe would have been thrown.”

viii. “Vimes opened the door to see what all the shouting was about down in the office. The corporal manning – or in this case dwarfing – the desk was having trouble.
‘Again? How many times have you been killed this week?’
‘I was minding my own business!’ said the unseen complainer.
‘Stacking garlic? You’re a vampire, aren’t you? I mean, let’s see what jobs you have been doing … Post sharpener for a fencing firm, sunglasses tester for Argus opticians … Is it me, or is there some underlying trend here?'”

ix. “‘Who was that little man with the incredibly bandy legs?’
‘That was Doughnut Jimmy, sir. He used to be a jockey on a very fat horse.’
‘A racehorse?’
‘Apparently, sir.’
‘A fat racehorse? Surely that could never win a race?’
‘I don’t believe it ever did, sir. But Jimmy made a lot of money by not winning races.'”

x. “This was police work, was it? He wondered if Mr Vimes was trying to tell him something. There were other letters. The Community Co-ordinator of Equal Heights for Dwarfs was demanding that dwarfs in the Watch be allowed to carry an axe rather than the traditional sword, and should be sent to investigate only those crimes committed by tall people. The Thieves’ Guild was complaining that Commander Vimes had said publicly that most thefts were committed by thieves.”

xi. “At the end of Nonesuch Street was a gibbet, where wrongdoers – or, at least, people found guilty of wrongdoing – had been hung to twist gently in the wind as examples of just retribution and, as the elements took their toll, basic anatomy as well.
Once, parties of children were brought there by their parents to learn by dreadful example of the snares and perils what await the criminal, the outlaw and those who happen to be in the wrong place at the wrong time, and they would see the terrible wreckage creaking on its chain and listen to the stern imprecations and then usually (this being Ankh-Morpork) would say ‘Wow! Brilliant!‘ and use the corpse as a swing. These days the city had more private and efficient ways of dealing with those it found surplus to requirements”

xii. “Colon in particular had great difficulty with the idea that you went on investigating after someone had confessed. You got a confession and there it ended. You didn’t go around disbelieving people. You disbelieved people only when they said they were innocent. Only guilty people were trustworthy. Anything else struck at the whole basis of policing.”

xiii. “he distrusted the kind of person who’d take one look at another man and say in a lordly voice to his companion, ‘Ah, my dear sir, I can tell you nothing except that he is a left-handed stonemason who has spent some years in the merchant navy and has recently fallen on hard times,’ and then unroll a lot of supercilious commentary about calluses and stance and the state of a man’s boots, when exactly the same comments could apply to a man who was wearing his old clothes because he’d been doing a spot of home bricklaying for a new barbecue pit, and had been tattooed once when he was drunk and seventeen* and in fact got seasick on a wet pavement. What arrogance! What an insult to the rich and chaotic variety of the human experience!'” [hmm… I’m wondering if Pratchett had anyone particular in mind when he wrote that]

xiv. “‘Life has certainly been more reliable under Vetinary,’ said Mr Potts of the Bakers’ Guild.
‘He does have all street-theatre players and mime artists thrown into the scorpion pit,’ said Mr Boggis of the Thieves’ Guild.
‘True. But let’s not forget that he has his bad points too.'”

xv. “I run a wholesome restaurant! My tables are so clean you could eat your dinner off them!’ […]
‘I told them, I use only the very best rats!’ shouted Gimlet. ‘Good plump rats from the best locations! None of your latrine rubbish! And they’re hard to come by, let me tell you!’
‘And when you can’t get them, Mr Gimlet?’ said Carrot.
Gimlet paused. Carrot was hard to lie to. ‘All right, he mumbled. ‘Maybe when there’s not enough I might sort of plump out the stock with some chicken, maybe just a bit of beef —‘
‘Hah! A bit?’ More voices were raised.
‘That’s right, you should see his cold room, Mr Carrot!’
‘Yeah, he uses steak and cuts little legs in it and covers it with rat sauce!’ […]

There were no public health laws in Ankh-Morpork. It would be like installing smoke detectors in Hell.”

xvi. “Every real copper knew you didn’t go around looking for Clues so that you could find out Who Done It. No, you started out with a pretty good idea of Who Done It. That way, you knew what Clues to look for.”

June 19, 2012 Posted by | books, Terry Pratchett | Leave a comment

Wikipedia articles of interest

i. Alternation of generations. It’s a bit technical, but I thought the article was interesting:

Alternation of generations (also known as alternation of phases or metagenesis) is a term primarily used to describe the life cycle of plants (taken here to mean the Archaeplastida). A multicellular sporophyte, which is diploid with 2N paired chromosomes (i.e. N pairs), alternates with a multicellular gametophyte, which is haploid with N unpaired chromosomes. A mature sporophyte produces spores by meiosis, a process which results in a reduction of the number of chromosomes by a half. Spores germinate and grow into a gametophyte. At maturity, the gametophyte produces gametes by mitosis, which does not alter the number of chromosomes. Two gametes (originating from different organisms of the same species or from the same organism) fuse to produce a zygote, which develops into a diploid sporophyte. This cycle, from sporophyte to sporophyte (or equally from gametophyte to gametophyte), is the way in which all land plants and many algae undergo sexual reproduction.

The relationship between the sporophyte and gametophyte varies among different groups of plants. In those algae which have alternation of generations, the sporophyte and gametophyte are separate independent organisms, which may or may not have a similar appearance. In liverworts, mosses and hornworts, the sporophyte is less well developed than the gametophyte, being entirely dependent on it in the first two groups. By contrast, the fern gametophyte is less well developed than the sporophyte, forming a small flattened thallus. In flowering plants, the reduction of the gametophyte is even more extreme; it consists of just a few cells which grow entirely inside the sporophyte.

All animals develop differently. A mature animal is diploid and so is, in one sense, equivalent to a sporophyte. However, an animal directly produces haploid gametes by meiosis. No haploid spores capable of dividing are produced, so neither is a haploid gametophyte. There is no alternation between diploid and haploid forms. […] Life cycles, such as those of plants, with alternating haploid and diploid phases can be referred to as diplohaplontic (the equivalent terms haplodiplontic, diplobiontic or dibiontic are also in use). Life cycles, such as those of animals, in which there is only a diploid phase are referred to as diplontic. (Life cycles in which there is only a haploid phase are referred to as haplontic.)

ii. Lightning. Long article, lots of stuff and links:

Lightning is an atmospheric electrical discharge (spark) accompanied by thunder, usually associated with and produced by cumulonimbus clouds, but also occurring during volcanic eruptions or in dust storms.[1] From this discharge of atmospheric electricity, a leader of a bolt of lightning can travel at speeds of 220,000 km/h (140,000 mph), and can reach temperatures approaching 30,000 °C (54,000 °F), hot enough to fuse silica sand into glass channels known as fulgurites, which are normally hollow and can extend as much as several meters into the ground.[2][3]

There are some 16 million lightning storms in the world every year.[4] Lightning causes ionisation in the air through which it travels, leading to the formation of nitric oxide and ultimately, nitric acid, of benefit to plant life below.

Lightning can also occur within the ash clouds from volcanic eruptions,[5] or can be caused by violent forest fires which generate sufficient dust to create a static charge.[1][6]

How lightning initially forms is still a matter of debate.[7] Scientists have studied root causes ranging from atmospheric perturbations (wind, humidity, friction, and atmospheric pressure) to the impact of solar wind and accumulation of charged solar particles.[4] Ice inside a cloud is thought to be a key element in lightning development, and may cause a forcible separation of positive and negative charges within the cloud, thus assisting in the formation of lightning.[4]

The irrational fear of lightning (and thunder) is astraphobia. The study or science of lightning is called fulminology, and someone who studies lightning is referred to as a fulminologist.[8] [I had no idea there was a name for this!] […]

An old estimate of the frequency of lightning on Earth was 100 times a second. Now that there are satellites that can detect lightning, including in places where there is nobody to observe it, it is known to occur on average 44 ± 5 times a second, for a total of nearly 1.4 billion flashes per year;[101][102] 75% of these flashes are either cloud-to-cloud or intra-cloud and 25% are cloud-to-ground.[103]

Approximately 70% of lightning occurs in the tropics where the majority of thunderstorms occur. The place where lightning occurs most often (according to the data from 2004–2005) is near the small village of Kifuka in the mountains of eastern Democratic Republic of the Congo,[105] where the elevation is around 975 metres (3,200 ft). On average this region receives 158 lightning strikes per 1 square kilometer (0.39 sq mi) a year.[102]

Above the Catatumbo river, which feeds Lake Maracaibo in Venezuela, Catatumbo lightning flashes several times per minute, 140 to 160 nights per year, accounting for 25% of the world’s production of upper-atmospheric ozone. Singapore has one of the highest rates of lightning activity in the world.[106] The city of Teresina in northern Brazil has the third-highest rate of occurrences of lightning strikes in the world.”

iii. Dreadnought (featured).

“The dreadnought was the predominant type of battleship in the early 20th-century. The first of the kind, the Royal Navy‘s Dreadnought, had such an impact when launched in 1906 that similar battleships built after her were referred to as “dreadnoughts”, and earlier battleships became known as pre-dreadnoughts. Her design had two revolutionary features: an “all-big-gun” armament scheme and steam turbine propulsion. The arrival of the dreadnoughts renewed the naval arms race, principally between the United Kingdom and Germany but reflected worldwide, as the new class of warships became a crucial symbol of national power. […]

While dreadnought-building consumed vast resources in the early 20th century, there was only one battle between large dreadnought fleets. At the Battle of Jutland, the British and German navies clashed with no decisive result. The term “dreadnought” gradually dropped from use after World War I, especially after the Washington Naval Treaty, as all remaining battleships shared dreadnought characteristics; it can also be used to describe battlecruisers, the other type of ship resulting from the dreadnought revolution.[1] […]

The building of Dreadnought coincided with increasing tension between the United Kingdom and Germany. Germany had begun to build a large battlefleet in the 1890s, as part of a deliberate policy to challenge British naval supremacy. With the conclusion of the Entente Cordiale between the United Kingdom and France in April 1904, it became increasingly clear that the United Kingdom’s principal naval enemy would be Germany, which was building up a large, modern fleet under the ‘Tirpitz’ laws. This rivalry gave rise to the two largest dreadnought fleets of the pre-war period.[93]

The first German response to Dreadnought came with the Nassau class, laid down in 1907. This was followed by the Helgoland class in 1909. Together with two battlecruisers—a type for which the Germans had less admiration than Fisher, but which could be built under authorization for armored cruisers, rather than capital ships—these classes gave Germany a total of ten modern capital ships built or building in 1909. While the British ships were somewhat faster and more powerful than their German equivalents, a 12:10 ratio fell far short of the 2:1 ratio that the Royal Navy wanted to maintain.[94]

In 1909, the British Parliament authorized an additional four capital ships, holding out hope Germany would be willing to negotiate a treaty about battleship numbers. If no such solution could be found, an additional four ships would be laid down in 1910. Even this compromise solution meant (when taken together with some social reforms) raising taxes enough to prompt a constitutional crisis in the United Kingdom in 1909–10. In 1910, the British eight-ship construction plan went ahead, including four Orion (1910)-class super-dreadnoughts, and augmented by battlecruisers purchased by Australia and New Zealand. In the same period of time, Germany laid down only three ships, giving the United Kingdom a superiority of 22 ships to 13. […]

The dreadnought race stepped up in 1910 and 1911, with Germany laying down four capital ships each year and the United Kingdom five. Tension came to a head following the German Naval Law of 1912. This proposed a fleet of 33 German battleships and battlecruisers, outnumbering the Royal Navy in home waters. To make matters worse for the United Kingdom, the Imperial Austro-Hungarian Navy was building four dreadnoughts, while the Italians had four and were building two more. Against such threats, the Royal Navy could no longer guarantee vital British interests. The United Kingdom was faced with a choice of building more battleships, withdrawing from the Mediterranean, or seeking an alliance with France. Further naval construction was unacceptably expensive at a time when social welfare provision was making calls on the budget. Withdrawing from the Mediterranean would mean a huge loss of influence, weakening British diplomacy in the Mediterranean and shaking the stability of the British Empire. The only acceptable option, and the one recommended by First Lord of the Admiralty Winston Churchill, was to break with the policies of the past and make an arrangement with France. The French would assume responsibility for checking Italy and Austria-Hungary in the Mediterranean, while the British would protect the north coast of France. In spite of some opposition from British politicians, the Royal Navy organised itself on this basis in 1912.[96]

In spite of these important strategic consequences, the 1912 Naval Law had little bearing on the battleship force ratios. The United Kingdom responded by laying down ten new super-dreadnoughts in her 1912 and 1913 budgets—ships of the Queen Elizabeth and Revenge classes, which introduced a further step change in armament, speed and protection—while Germany laid down only five, focusing resources on the Army.[97]

iv. Travelling salesman problem.

“The travelling salesman problem (TSP) is an NP-hard problem in combinatorial optimization studied in operations research and theoretical computer science. Given a list of cities and their pairwise distances, the task is to find the shortest possible route that visits each city exactly once and returns to the origin city. It is a special case of the travelling purchaser problem.

The problem was first formulated as a mathematical problem in 1930 and is one of the most intensively studied problems in optimization. It is used as a benchmark for many optimization methods. Even though the problem is computationally difficult, a large number of heuristics and exact methods are known, so that some instances with tens of thousands of cities can be solved.

The TSP has several applications even in its purest formulation, such as planning, logistics, and the manufacture of microchips. Slightly modified, it appears as a sub-problem in many areas, such as DNA sequencing. In these applications, the concept city represents, for example, customers, soldering points, or DNA fragments, and the concept distance represents travelling times or cost, or a similarity measure between DNA fragments. In many applications, additional constraints such as limited resources or time windows make the problem considerably harder. […]

The most direct solution would be to try all permutations (ordered combinations) and see which one is cheapest (using brute force search). The running time for this approach lies within a polynomial factor of O(n!), the factorial of the number of cities, so this solution becomes impractical even for only 20 cities. One of the earliest applications of dynamic programming is the Held–Karp algorithm that solves the problem in time O(n22n).[13] […]

An exact solution for 15,112 German towns from TSPLIB was found in 2001 using the cutting-plane method proposed by George Dantzig, Ray Fulkerson, and Selmer M. Johnson in 1954, based on linear programming. The computations were performed on a network of 110 processors located at Rice University and Princeton University (see the Princeton external link). The total computation time was equivalent to 22.6 years on a single 500 MHz Alpha processor. In May 2004, the travelling salesman problem of visiting all 24,978 towns in Sweden was solved: a tour of length approximately 72,500 kilometers was found and it was proven that no shorter tour exists.[16]

In March 2005, the travelling salesman problem of visiting all 33,810 points in a circuit board was solved using Concorde TSP Solver: a tour of length 66,048,945 units was found and it was proven that no shorter tour exists. The computation took approximately 15.7 CPU-years (Cook et al. 2006). In April 2006 an instance with 85,900 points was solved using Concorde TSP Solver, taking over 136 CPU-years […]

Various heuristics and approximation algorithms, which quickly yield good solutions have been devised. Modern methods can find solutions for extremely large problems (millions of cities) within a reasonable time which are with a high probability just 2–3% away from the optimal solution.”

v. Ediacara biota (featured).

“The Ediacara (play /ˌdiˈækərə/; formerly Vendian) biota consisted of enigmatic tubular and frond-shaped, mostly sessile organisms which lived during the Ediacaran Period (ca. 635–542 Ma). Trace fossils of these organisms have been found worldwide, and represent the earliest known complex multicellular organisms.[note 1] The Ediacara biota radiated in an event called the Avalon Explosion, 575 million years ago,[1][2] after the Earth had thawed from the Cryogenian period’s extensive glaciation, and largely disappeared contemporaneously with the rapid appearance of biodiversity known as the Cambrian explosion. Most of the currently existing body-plans of animals first appeared only in the fossil record of the Cambrian rather than the Ediacaran. For macroorganisms, the Cambrian biota completely replaced the organisms that populated the Ediacaran fossil record.

The organisms of the Ediacaran Period first appeared around 585 million years ago and flourished until the cusp of the Cambrian 542 million years ago when the characteristic communities of fossils vanished. The earliest reasonably diverse Ediacaran community was discovered in 1995 in Sonora, Mexico, and is approximately 585 million years in age, roughly synchronous with the Gaskiers glaciation.[3] While rare fossils that may represent survivors have been found as late as the Middle Cambrian (510 to 500 million years ago) the earlier fossil communities disappear from the record at the end of the Ediacaran leaving only curious fragments of once-thriving ecosystems.[4] Multiple hypotheses exist to explain the disappearance of this biota, including preservation bias, a changing environment, the advent of predators and competition from other life-forms.

Determining where Ediacaran organisms fit in the tree of life has proven challenging; it is not even established that they were animals, with suggestions that they were lichens (fungus-alga symbionts), algae, protists known as foraminifera, fungi or microbial colonies, to hypothetical intermediates between plants and animals. The morphology and habit of some taxa (e.g. Funisia dorothea) suggest relationships to Porifera or Cnidaria.[5] Kimberella may show a similarity to molluscs, and other organisms have been thought to possess bilateral symmetry, although this is controversial. Most macroscopic fossils are morphologically distinct from later life-forms: they resemble discs, tubes, mud-filled bags or quilted mattresses. Due to the difficulty of deducing evolutionary relationships among these organisms some paleontologists have suggested that these represent completely extinct lineages that do not resemble any living organism. One paleontologist proposed a separate kingdom level category Vendozoa (now renamed Vendobionta)[6] in the Linnaean hierarchy for the Ediacaran biota. If these enigmatic organisms left no descendants their strange forms might be seen as a “failed experiment” in multicellular life with later multicellular life independently evolving from unrelated single-celled organisms.[7]

Terms like ‘may have’ (9), ‘perhaps’ (3) and ‘probably’ (3) are abundant in the article, but think about how long time ago this was. I think it’s frankly just incredibly awesome that we even know anything at all.

vi. Three Emperors Dinner. Yes, there’s a Wikipedia article about a dinner that happened more than 100 years ago. Wikipedia is awesome!

“The Dîner des trois empereurs or Three Emperors Dinner was a banquet held at Café Anglais in Paris, France on 7 June 1867.

It was prepared by chef Adolphe Dugléré at the request of King William I of Prussia who frequented the cafe during the Exposition Universelle. He requested a meal to be remembered and at which no expense was to be spared for himself and his guests, Tsar Alexander II of Russia, plus his son the tsarevitch (who later became Tsar Alexander III), and Prince Otto von Bismarck. The cellar master, Claudius Burdel, was instructed to accompany the dishes with the greatest wines in the world, including a Roederer champagne in a special lead glass bottle, so Tsar Alexander could admire the bubbles and golden colour.[1]

The banquet consisted of 16 courses with eight wines served over eight hours. The cost of the meal was 400 francs per person[2] (about 8,800 in 2012 prices).”

June 17, 2012 Posted by | biology, genetics, history, mathematics, Paleontology, wikipedia | Leave a comment

Ideas

“Me: In my opinion it’s really hard to have interesting ideas if you don’t write them down. It’s much, much easier to spot flaws in your reasoning, to add complexity, to take account of -ll- if you write things down.

A friend: I quite agree

Me: It quickly became an argument for keeping my blog alive, back when I wrote a lot of stuff myself rather than leech off the ideas of others as is mostly the case now.

A friend: Why don’t you write more of your own ideas then?

Me: They are not interesting […] I’d much rather share knowledge with other people than [my] ideas.”

I know I shouldn’t quote myself, nor should I quote a friend who has not even agreed to be quoted. But I thought I’d put that out there anyway, because this is probably something people should have realized by now. There are people who happen to be quite good at getting good ideas, good at thinking about stuff. I realized a long time ago that I am not one of those people, and that I would be wise to limit myself to quoting the ideas of the people who know how to get good ideas, and otherwise just keep my mouth shut. Or share data, which amounts to the same thing when it comes to that. I sometimes fail and I open my mouth anyway, and I do it because I like to think about stuff and I do it a lot. But I’m well aware that there are lots of people who are much better at it than I am and that I really should try not to waste people’s time and humiliate myself in the process.

I know, but sometimes I just don’t care, so here’s something I’ve had on my mind for a while. I’m often asked ‘how I feel.’ We all know that question, and we all know how to answer it. Even a person like me is not unaware of the social conventions related to how you’re supposed to approach that question. So I usually answer ‘okay,’ ‘reasonable’, ‘not bad’ or something like that. It’s what people do.

But such questions always bother me a bit. There are two reasons. The first one is the rather obvious one that well, really, most of the time I have no idea how I feel. I need to think about that question in order to answer it, and the amount of time I’d need to give any kind of semi-sensible answer to the question is way more time than the amount of time that is usually allotted to the purpose, given the social context. Perhaps my emotional states are not as readily available to me as they might be to some people. A related concern here is that it is of course very unpleasant to feel the need to answer a question to which you don’t know the answer, and to be placed in a situation where you’re very aware of the fact that you seem to be trying to guess the teacher’s password. This is a situation you generally try to avoid. The problem is perhaps exacerbated even further by the fact that when I actually do spend time thinking about how I’m feeling in other contexts, quite often it is an activity which is predicated upon the fact that I, well, do not feel good at all; and getting asked how you feel when this is the way things usually work can be unpleasant, because getting asked that question can easily remind you that you’re in fact not as happy as you’d like to be. And then it’s easy to mentally jump along to the question of why you’re not as happy as you’d like to be, and most of the time there are lots of good reasons why you don’t seem to have anybody to blame for this sad state of affairs but yourself. But then you might go even further and argue that you do have happy moments sometimes, and that you’ve actually done some work on actively figuring out when they happen, as they happen – ‘this is a pleasurable moment’-type thinking – and what you’re doing when they happen, and this seems to help you and really there’s no good reason why you should not be having such a moment within a short amount of time and… Meanwhile, the person who asked the question is still waiting for an answer.

The other big reason why such questions bother me a bit is that I have no way of knowing if the answer even makes sense to the person to whom I’m responding, even if I do answer truthfully (which would require a complex and rather detailed answer). How do they define ‘feeling good/ok/not bad/reasonable’? I have never looked inside their heads or hearts, I don’t know the emotional range they inhabit very well. Maybe my answer is completely meaningless to them. Do people have well-defined emotional barometers where you can just go have a look and see; ‘oh – so that’s how you feel, 37°, that’s interesting…’ No, they don’t. Even in the best of cases it’s hard to figure out if the answer you give is actually conveying the information you’d like to share. And the real world don’t do with the best of cases, because I usually don’t answer truthfully, a fact I have no problem sharing here. I always have doubts, regrets and self-hatred bubbling under the surface, and I work on keeping those things far away from my own inner monologue; why in the world would I want to bring them out into polite conversations which take place outside my own head, with people who have perhaps no idea what they are getting themselves into?

I’m quite curious as to how people handle and understand their emotional states. Do people actually walk around knowing ‘how they fell’? I know I don’t and I have a hard time imagining that many other people do. It would be nice if people settled upon a different casual conversation starter – most people who ask this question don’t really want to know anyway.

June 15, 2012 Posted by | personal, rambling nonsense | 10 Comments

Relationships and income – some thoughts

I really don’t know what the literature has to say about this stuff (there has to be a literature on this, even though I didn’t find much while looking for it..), but I had a discussion earlier today where some things related to the stuff below came up. Here are some thoughts that developed in my mind while I was grocery shopping a little while ago. I added a few other points as well at the bottom. I’m sure this is all very basic, but it’s easy to miss the obvious if you don’t actively think about stuff like this every now and then:

i. When it comes to income and relationships, my assumption would be that the potential set of partners available to an individual is more or less strictly increasing in the income of that individual. The richer you are, the more potential partners are available to you. This is because a marginal increase in income will pretty much never cause you to be considered less desirable on average (ceteris paribus). Even if this for some reason should not hold at the relevant boundary point, it’s trivial to show that in case the wealth of an individual is so high as to somehow harm the relationship opportunities of said individual, the decrease in relationship opportunities caused by this wealth level should be considered an entirely voluntary cost of being so rich; one can always get rid of ‘extra money’ in case it harms one’s opportunities. The wealth level should always have a positive impact on the relationship opportunities of a financially unrestrained optimizing agent.

ii. One thing worth noting is that whereas in some contexts income is a perfectly reasonable variable to work with, in other contexts it makes more sense to work with income differentials between potential partners because these will sometimes be more important. If the potential partner is a billionaire, she’ll not be impressed by his money when a mere millionaire approaches her. Also, I remember having read at one point that there’s an increased risk of divorce if the female earns more than the male (but I’m too lazy to look for the study right now).

iii. The effect of money on relationship opportunities is much stronger for men than for women.

iv. Threshold effects matter both at the lower end and at the upper end of the income distribution. In Denmark income inequality is low, so this part of the equation is probably less relevant than it is a lot of other places. Nevertheless, the jump from ‘uncertain unemployment situation’ or similar to ‘stable long-term provider’ I assume will normally add a lot of relationship brownie points, at least when considering the situation of a single male. On the other hand, the difference between ‘incredibly rich’ and ‘insanely rich’ isn’t that big of a deal.

v. The more potential partners are available to you, and/or the more potential partners you believe are available to you, the more you adjust your criteria for what constitutes an acceptable mate; i.e. the more options you have, the more picky you get.

vi. People, especially but not only females, who believe themselves to be high-quality partner material often forget about v. They like to tell themselves that they have few options, whereas in reality they have a lot of options, options which they are disregarding. A big part of what constrains their choice sets seems to be their own preferences. Cultural mores seem to encourage and enforce such behaviour.

vii. Education has become a much more important signalling device than it was in the past. Again, female preferences seem to matter more than do those of the males, so education is a more important variable for a male looking for a partner than for a female. Females generally seem to dislike the idea of marrying males with a lower level of education. See also v. When it comes to relationship dynamics, the difference in education level between two potential partners is arguably an even more important variable than is the income differential.

viii. In the relationship context, BMI and similar metrics matter significantly more for females than males. It therefore makes good sense that far more males than females are overweight. I’m sure that’s not the only reason, but…

ix. In general, age matters a lot more when it comes to the relationship opportunities of young and middle-aged females than when it comes to -ll- males.

x. In general, when people think they have more options they become less likely to commit and more likely to break up a relationship which does not match their expectations. High self-perceived relationship potential might actually cause behaviour which is most often associated with people at the opposite end of the relationship potential spectrum. This is of course again closely related to v.

June 15, 2012 Posted by | dating, random stuff | Leave a comment

That is a lot of hours…

According to some new stats from Statistics Denmark, Danes spend on average 3 hours and 18 minutes watching TV every day. I got curious and so decided to take a closer look at the numbers. The numbers below are based on ‘FOR4215: Gennemsnitlig dagligt tv-forbrug i minutter (3 år+) efter måned’ from Statistikbanken.

It’s a quite interesting jump. What about variation during the year? Well, we watch more TV during the winter months, but actually I’d have guessed beforehand that the variation was bigger than it seems to be:

Danes watch more hours of TV2 than they watch hours of DR1, on an annual basis (FOR4213: Seertid (i minutter) efter tv-kanal og programtype). In 2011, they watched 16.806 minutes of TV2 on average (~46 minutes/day) and 12.945 minutes of DR1 (~35). I would have thought these numbers were higher, because they still leave a lot of hours unaccounted for.

This is one of those areas where I don’t mind being below average.

June 14, 2012 Posted by | data, demographics, denmark | Leave a comment

Another book

I was thinking a bit about whether I should post this in Danish or English, as it’s a comment on a book in Danish. In the end I figured that I wouldn’t write very much about it anyway and I didn’t want the non-Danes to feel excluded, so I decided to post in English.

The book is Ergo – Naturvidenskabens filosofiske historie,  and I do not recommend it – certainly not to people remotely like me – even though I haven’t read it to the end yet (though I did read the first 300 pages yesterday). It doesn’t contain a lot of stuff I didn’t already know, there’s a lot of unclear waffling along the way and frankly, I just don’t find that the optimal working assumption when reading this is even that the authors understand/are right about all the stuff they write about. I guess it’s okay if you want a book that covers a lot of names/concepts which you can then start reading about other places. But how can you take very seriously a book about natural science and philosophy written by people who don’t know how old the Earth is? Maybe you can; I can’t. I consider it light reading, entertainment, even though I’m very certain it wasn’t meant to be read as such. Perceived in this light, it’s not that bad but I refuse to recommend it:

“Hvis man forestillede sig, at hele jordklodens masse siden dens dannelse for 3,8 milliarder år siden var blevet brugt…” (‘if one imagined that the entire mass of the Earth since its formation 3.8 billion years ago had been used…’).

The difference between this given age of the Earth and the true age of the Earth (4.54 × 109 years ± 1%) is 740 million years. Take a look here and see what happens if you shave away the last 700+ million years of the history of the Earth – this is how wrong that sentence is. It’s more than 3 galactic years wrong. Maybe they meant something differently, but that’s not really a defence – the language in the book is sometimes unclear, in part because they use terms without defining them first. A lot of places it lacks clarity. There are other issues as well. I’m disappointed, but I’ll probably read it to the end anyway. If it was written in English I wouldn’t, but it seems that it takes almost no time to read stuff like this in Danish when you’re not actively studying.

Update: I’ve completed the book. Nothing I read in the last 120 pages has made me reconsider. If anything, I think less of the book than I did before. Don’t read this.

June 14, 2012 Posted by | books | 2 Comments

Hogfather

by Terry Pratchett. I  read a few hours yesterday and then completed it today. I’d forgotten how fast you go through books like these, compared to textbooks; I got so curious after a bit of reading that I decided to time myself, and my best estimate – based on 5 hours of reading – is that on average I read about 60 pages an hour, or one page/minute. So the fact that it will take you ‘a long time’ to read this book is no excuse for not reading it, because it simply won’t (but don’t start out with this one if you’ve never read Pratchett before).

Some quotes from the book:

“The senior wizards of Unseen University stood and looked at the door.
There was no doubt that whoever had shut it wanted it to stay shut. Dozens of nails secured it to the door frame. Planks had been nailed right across. And finally it had, up until this morning, been hidden by a bookcase that had been put in front of it.
‘And there’s the sign, Ridcully,’ said the Dean. ‘You have read it, I assume. You know? The sign which says “Do not, under any circumstances, open this door”?’
‘Of course I’ve read it,’ said Ridcully. ‘Why d’yer think I want it opened?’
‘Er … why?’ said the Lecturer in Recent Runes.
‘To see why they wanted it shut, of course.’*
[*This exchange contains almost all you need to know about human civilization. At least, those bits of it that are now under the sea, fenced off or still smoking.]”

“Lord Downey was an assassin. Or, rather, an Assassin. The capital letter was important. […] The members of the Guild of Assassins considered themselves cultured men who enjoyed good music and food and literature. And they knew the value of human life. To a penny, in many cases. […] Anyone could buy the services of the Guild. Several zombies had, in the past, employed the Guild to settle scores with their murderers. In fact the Guild, he liked to think, practised the ultimate democracy. You didn’t need intelligence, social position, beauty or charm to hire it. You just needed money which, unlike the other stuff, was available to everyone. Except for the poor, of course, but there was no helping some people.”

“There were lessons later on. These were going a lot better now she’d got rid of the reading books about bouncy balls and dogs called Spot. She’d got Gawain on to the military campaigns of General Tacticus, which were suitably bloodthirsty but, more importantly, considered too difficult for a child. As a result his vocabulary was doubling every week and he could already use words like ‘disembowelled’ in everyday conversation. After all, what was the point of teaching children to be children? They were naturally good at it.”

“‘There used to be warning signs up,’ said the neat voice from behind. ‘Yeah, well, warning signs in Ankh-Morpork might as well have “Good Firewood” written on them'”.

“Susan didn’t like Biers but she went there anyway, when the pressure of being normal got too much. Biers, despite the smell and the drink and the company, had one important virtue. In Biers nobody took any notice. Of anything. Hogswatch was traditionally supposed to be a time for families but the people who drank in Biers probably didn’t have families; some of them looked as though they might have had litters, or clutches. Some of them looked as though they’d probably eaten their relatives, or at least someone‘s relatives.
Biers was where the undead drank. And when Igor the barman was asked for a Bloody Mary, he didn’t mix a metaphor.”

[when reading this, think of the Hogfather as Discworld’s Santa Claus…]
“‘This is a shop,’ said Mr Crumley, finally getting to the root of the problem. ‘We do not give Merchandise away. How can we expect people to buy things if some Person is giving them away? Now please go and get him out of here.’
‘Arrest the Hogfather, style of thing?’
‘Yes!’
‘On Hogswatchnight?’
‘Yes!’
‘In your shop?’
Yes!’
‘In front of all those kiddies?’
‘Y—‘ Mr Crumley hesitated. To his horror, he realized that Corporal Nobbs, against all expectation, had a point.”

“The Archchancellor pointed dramatically skywards. ‘To the laundry!’ he said. ‘It’s downstairs, Ridcully,’ said the Dean. ‘Down to the laundry!’ ‘And you know Mrs Whitlow doesn’t like us going in there,’ said the chair of Indefinite Studies. ‘And who is Archchancellor of this University, may I ask?’ said Ridcully. ‘Is it Mrs Whitlow? I don’t think so! Is it me? Why, how amazing, I do believe it is!’ ‘Yes, but you know what she can be like,’ said the Chair. ‘Er, yes, that’s true—‘ Ridcully began. ‘I believe she’s gone to her sister’s for the holiday,’ said the Bursar. ‘We certainly don’t have to take orders from any kind of housekeeper!’ said the Archchancellor. ‘To the laundry!’
The wizards surged out excitedly, leaving Susan, the oh god, the Verruca Gnome and the Hair Loss Fairy. ‘Tell me again who those people were,’ said the oh god. ‘Some of the cleverest men in the world,’ said Susan.

“I THINK I MUST TELL YOU SOMETHING, said Death. ‘Yes, I think you should,’ said Ridcully. ‘I’ve got little devils running round the place eating socks and pencils, earlier tonight we sobered up someone who thinks he’s a God of Hangovers and half my wizards are trying to cheer up the Cheerful Fairy. We thought something must’ve happened to the Hogfather. We were right, right?’

“‘I’m sure he wouldn’t keep on eating them if they were addictive,’ said the Senior Wrangler.”

“‘I really should talk to him, sir. He’s had a near-death experience!’ ‘We all have. It’s called “living”,'”

Lastly, a quote which also made it into the movie (even if in a somewhat abbreviated form):

June 12, 2012 Posted by | books, quotes/aphorisms, Terry Pratchett | 4 Comments

Stuff (updated)

(After Ed Yong published his latest post, I decided to add a couple of links – Monday, 10 a.m.)

i. Introduction to Evolutionary Biology (TalkOrigins)

I read this yesterday, I’m sure some of you will find it to be useful. Some quotes:

“Populations evolve. [evolution: a change in the gene pool] In order to understand evolution, it is necessary to view populations as a collection of individuals, each harboring a different set of traits. A single organism is never typical of an entire population unless there is no variation within that population. Individual organisms do not evolve, they retain the same genes throughout their life. When a population is evolving, the ratio of different genetic types is changing — each individual organism within a population does not change. For example, in the previous example, the frequency of black moths increased; the moths did not turn from light to gray to dark in concert. The process of evolution can be summarized in three sentences: Genes mutate. [gene: a hereditary unit] Individuals are selected. Populations evolve.

Evolution can be divided into microevolution and macroevolution. The kind of evolution documented above is microevolution. Larger changes, such as when a new species is formed, are called macroevolution. Some biologists feel the mechanisms of macroevolution are different from those of microevolutionary change. Others think the distinction between the two is arbitrary — macroevolution is cumulative microevolution.

The word evolution has a variety of meanings. The fact that all organisms are linked via descent to a common ancestor is often called evolution. The theory of how the first living organisms appeared is often called evolution. This should be called abiogenesis. And frequently, people use the word evolution when they really mean natural selection — one of the many mechanisms of evolution. […]

Evolution can occur without morphological change; and morphological change can occur without evolution. Humans are larger now than in the recent past, a result of better diet and medicine. Phenotypic changes, like this, induced solely by changes in environment do not count as evolution because they are not heritable; in other words the change is not passed on to the organism’s offspring. […]

Evolution is not progress. Populations simply adapt to their current surroundings. They do not necessarily become better in any absolute sense over time. A trait or strategy that is successful at one time may be unsuccessful at another.” […]

Organisms are not passive targets of their environment. Each species modifies its own environment. At the least, organisms remove nutrients from and add waste to their surroundings. Often, waste products benefit other species. Animal dung is fertilizer for plants. Conversely, the oxygen we breathe is a waste product of plants. Species do not simply change to fit their environment; they modify their environment to suit them as well. […]

Natural selection may not lead a population to have the optimal set of traits. In any population, there would be a certain combination of possible alleles that would produce the optimal set of traits (the global optimum); but there are other sets of alleles that would yield a population almost as adapted (local optima). Transition from a local optimum to the global optimum may be hindered or forbidden because the population would have to pass through less adaptive states to make the transition. Natural selection only works to bring populations to the nearest optimal point. This idea is Sewall Wright’s adaptive landscape. This is one of the most influential models that shape how evolutionary biologists view evolution. […]

Sexual selection is natural selection operating on factors that contribute to an organism’s mating success. Traits that are a liability to survival can evolve when the sexual attractiveness of a trait outweighs the liability incurred for survival. A male who lives a short time, but produces many offspring is much more successful than a long lived one that produces few. The former’s genes will eventually dominate the gene pool of his species. In many species, especially polygynous species where only a few males monopolize all the females, sexual selection has caused pronounced sexual dimorphism. In these species males compete against other males for mates. The competition can be either direct or mediated by female choice. In species where females choose, males compete by displaying striking phenotypic characteristics and/or performing elaborate courtship behaviors. The females then mate with the males that most interest them, usually the ones with the most outlandish displays. There are many competing theories as to why females are attracted to these displays.” (In humans, females choose so this could be construed as another bit of dating advice to add to this post…) […]

“Most mutations that have any phenotypic effect are deleterious. Mutations that result in amino acid substitutions can change the shape of a protein, potentially changing or eliminating its function. This can lead to inadequacies in biochemical pathways or interfere with the process of development. Organisms are sufficiently integrated that most random changes will not produce a fitness benefit. Only a very small percentage of mutations are beneficial.”

There’s a lot more at the link. Not all of it belongs in the ‘all people who know anything about evolutionary biology would agree on this 100 percent’-category [one example: “Genes are not the unit of selection (because their success depends on the organism’s other genes as well); neither are groups of organisms a unit of selection. There are some exceptions to this “rule,” but it is a good generalization.” – not everybody ‘in the field’ would agree with that], but most of it is relatively incontestable and it covers a lot of ground; a huge number of key concepts are explained and elaborated upon here. Read it, but don’t start reading it before you’re in a situation where you have a decent amount of time to spare. No matter how well-read you are, unless you’ve actually read this piece before odds are you’ll not know everything which is covered here – for instance, you probably didn’t know that “over half of all named species are insects. One third of this number are beetles.” I know I didn’t. The article was written a while ago, so I decided to check up on the data – here’s what wikipedia has to say about the matter today: “Even though the true dimensions of species diversity remain uncertain, estimates are ranging from 1.4 to 1.8 million species. […] About 850,000–1,000,000 of all described species are insects.” I should probably point out that even though it’s written in a manner-of-fact like way all the way through, he incidentally doesn’t exactly beat about the bush at the end:

“Scientific creationism is 100% crap. So-called “scientific” creationists do not base their objections on scientific reasoning or data. Their ideas are based on religious dogma, and their approach is simply to attack evolution. The types of arguments they use fall into several categories: distortions of scientific principles ( the second law of thermodynamics argument), straw man versions of evolution (the “too improbable to evolve by chance” argument), dishonest selective use of data (the declining speed of light argument) appeals to emotion or wishful thinking (“I don’t want to be related to an ape”), appeals to personal incredulity (“I don’t see how this could have evolved”), dishonestly quoting scientists out of context (Darwin’s comments on the evolution of the eye) and simply fabricating data to suit their arguments (Gish’s “bullfrog proteins”).

Most importantly, scientific creationists do not have a testable, scientific theory to replace evolution with. Even if evolution turned out to be wrong, it would simply be replaced by another scientific theory.”

As can also be inferred from the links at the end, this is not the only post of its kind at TalkOrigins. Go have a look if you’re even remotely interested!

ii. Two figures:

(link).

iii. How far do Danes commute to go to work? Answer: It varies.

The table includes the Danish municipalities with the ten highest and lowest average commuting distances. The distances given in the table are the distances between the homes of the commuters and their workplaces, not the distances travelled on an average day (which would be twice that number). Local or regional wage differentials and corresponding differences in opportunity cost of time definitely plays a role here. Note that ‘distance travelled’ is not necessarily a good proxy for ‘time spent commuting’, especially not when comparing the commutes of people living in urban areas with those of people living in rural areas (ceteris paribus, d(commuting time)/d(pop-density)>0). The numbers are from this new publication by Statistics Denmark, which also included this map of the gender differences across the country (yellow: the average male commute is less than 6 kilometers longer than the average female commute, etc. The darker, the bigger the difference between the genders..):

The national average commuting distance to work is ~20 km (19.7). The male average is 23.4 km, the female average is 15.9 km.

iv. This should all be known stuff to you guys, but in case it’s not:

v. A number: 27.5% of all inmates in Danish prisons are foreign citizens (article in Danish here). Foreign citizens make up about 7,7% of the population. If you look closer, I’m positive both that you’ll find huge variation across countries, and that you’ll also find that some immigrant groups are significantly less likely to commit crimes than are people with Danish citizenship.

vi. The Long, Fake Life of J.S. Dirr. An internet hoax that survived for 11 years, from the very beginning of social medias almost to the present day. Interesting.

vii. Why You Can’t Kill a Mosquito with a Raindrop. Add this one to the list of questions I had never even thought about asking. Fascinating stuff, a few quotes:

“the consequence of getting hit by a raindrop depends on what part of the mosquito’s body takes the blow. Since the insects are so lanky, 75% of hits happen on the legs or wings. This can throw a mosquito into a brief tumble or even a barrel roll, but it recovers without much trouble.

Direct hits to mosquitos’ bodies are a different kind of carnival ride. The speeding raindrops glom onto the insects and propel them downward. Mosquitos captured on camera sometimes fell as far as 20 body lengths while being pushed by a raindrop. For a human, that would be a 12-story drop and a quick ending to the story. But mosquitos are able to pull away sideways from the raindrops and continue on their way, unharmed.

The only danger seems to come if mosquitos are flying close to the ground when they’re hit, leaving themselves too little time to escape. The authors note that one unlucky bug was driven into a puddle and “ultimately perished.” […]

When the heavy drop hits the airy mosquito, it’s almost like hitting nothing at all. And this, the researchers found, is what keeps the mosquitos alive. By offering barely any resistance, a mosquito minimize the force of the collision. The raindrop doesn’t even splatter when it hits. […]

Humans being hurled downward generally black out around 2 or 3 G’s. But a mosquito suddenly driven toward the ground by a raindrop experiences an acceleration of 100 to 300 G’s. The authors note that “insects struck by rain may achieve the highest survivable accelerations in the animal kingdom.””

viii. TV Tropes tips for writers.

June 10, 2012 Posted by | biology, data, demographics, evolution, genetics, Lectures, medicine, Pharmacology | Leave a comment

A reminder

I mostly post this because people rarely click the links in my sidebar (blogroll etc.) and I think some of you may be missing out on good stuff. So I decided to post a few quotes from more or less random posts at Katja Grace’ blog here, to give you a sense of why I’ve put a link to her blog on my blogroll. Some of her ideas I consider plain weird, but there’s a lot of good stuff too:

i. “people are uncomfortable comparing their friends and partners with others they might have had instead, and in the absence of comparison most people think those they love are pretty good. You rarely hear ‘there are likely about half a billion wives I would like more than you out there, but you are the one I’m arbitrarily in love with’.

This all makes evolutionary sense; blind loyalty is better than ongoing evaluation from an ally, at least towards you. So you evaluate people accurately for a bit, then commit to the good ones. Notice that here the motivation for not comparing appears to come from the benefits of committing to people without regret, rather than the difficulty of figuring out what a nice bottom is worth next to a good career.” (from Experiences are friends)

ii. “When we don’t have concepts for things, we can hardly think about them. When I learn new concepts, I often notice them applying everywhere where before I didn’t even notice anything missing. […] We don’t invent our own concepts very much; we mostly inherit them from our society. How many concepts that you have did you invent? If it is very few, this is probably not just because society has already found all the useful concepts and given them to you. If you lived a thousand years ago, my guess is that society wouldn’t have given you concepts like ‘subjective probability’ or ‘tragedy of the commons’ or ‘computation’. And no matter how nerdy you are, you probably wouldn’t have made them up. After all, a whole bunch of people did live then, and they didn’t make them up. […]

Hypothesis: We have relatively few concepts for the world inside our heads, because it’s not very shared, and we get concepts mostly from other people. This means it is hard to think about the world inside our heads, and so also hard to remember. (This is all relative to the world outside our heads, and relative to how we would be if we could show one another inside our heads more).” (from Are we infantile introspectors)

iii. “Why are aphorisms cynical more often than books are for instance?

A good single sentence saying can’t require background evidencing or further explanation. It must be instantly recognizable as true. It also needs to be news to the listener. Most single sentences that people can immediately verify as true they already believe. What’s left? One big answer is things that people don’t believe or think about much for lack of wanting to, despite evidence. Drawing attention to these is called cynicism.” (from Why do aphorisms and cynicism go together?)

iv. “Imagine you were aiming to appear to care about something or somebody else. One way you could do it is to work out exactly what would help them and do that. What could possibly look like you care about them more? The first problem here is that onlookers might not know what is really helpful, especially if you had to do any work to figure it out. So they won’t recognize your actions as being it. You would do better to do something that most people believe would be helpful than something that you know would.

Another problem arises if everyone knows the thing is helpful to others, but they also know that you could do the same thing to help yourself. From their perspective, you are probably helping yourself. Here you can solve both problems at once by just doing something that credibly doesn’t help you. People will assume there is some purpose, and if it’s not self serving it’s probably for someone else. You can demonstrate care better with actions which are obviously useless to you and plausibly useful to someone else than actions plausibly useful to you and obviously useful to someone else. Fasting to raise awareness for the hungry looks more sincere than eating to raise money for the hungry.” (from Being useless to express care)

v. “One way to be more satisfied with life is to lower your standards. People seem pretty hesitant to do this most of the time. And fair enough: who wants to be satisfied at the expense of everything else they care about? Happiness isn’t that great.

If only it were possible to feel like you had lower standards without actually settling for the very easiest career that would pay for your tent, noodles, and blow up companion.

I wonder if this is a significant reason people drink alcohol.

It seems that when people drink they lower their standards for many things. For what to laugh at, for what’s worth saying, and for who it’s worth saying to, for instance. They enthusiastically eat things they would find barely passable sober, and are thrilled by activities they usually find beneath them.

Yet this standard lowering is constrained in time, so as long as you don’t become permanently intoxicated you can spend most of your days having high standards. And since there was a specific identifiable reason for your low standards (even if purely social), it need not contaminate your image as a discerning person. At least not as much.

Is this an actual common point of drinking, or just a side effect? I don’t know – I don’t drink enough, and apparently this isn’t considered a good topic of party conversation.” (from Drinking to lower standards?)

 

June 8, 2012 Posted by | blogs, quotes/aphorisms | Leave a comment

Promoting the unknown, a continuing series

I recently discovered Ferdinand Ries and all the pieces below are by him:

June 7, 2012 Posted by | music | Leave a comment

Dating advice (not from me)

Given that the person who wrote the post to which I’m linking did not manage to convince me to change my mind about this even after a relatively long discussion earlier today, the advice will probably not be of much relevance to me, at least not if I’m successful. But maybe you’ll be able to make use of it, and even if you’re not dating some of it can also be applied in other social contexts as well (link):

“If you want my opinion, I think everything can actually be very simple (though perhaps I’ll be disillusioned once I become more acquainted with the dating scene). You can pare things down to just a few friendly maxims; they don’t have to be so complicated. Now, please brace yourself for some hackneyed words of ‘wisdom’, coming from yours truly:

If you want to appear totally awesome in front of someone for whom you have non-platonic feelings, then just strive to be awesome at all times. If you want to be able to engage in meaningful and intelligent conversations, then just cultivate a habit to read more, watch more news and documentaries, ask more meaningful questions and learn more. If you want to show how attuned and sensitive you are to artistic endeavours and perspectives, then just open your eyes wider and try to seek beauty in all the corners of your everyday life. If you want to establish yourself as a connoisseur of the good things in life, it would be ideal to start being more appreciative of the little luxuries you enjoy. If you want to portray yourself as a thoughtful and patient person, then just keep reminding yourself to distribute more kindness to others whenever possible, and to be more empathetic towards other people’s suffering. If you want to exuberate confidence, then just try your very best to develop the courage to stand up for your own principles when necessary, and to have more self-esteem. In daily life you should always aim for perfection, so that you don’t have to go through any charade when you are hanging out with someone in whom you are interested.

Being intellectual isn’t about going to great lengths to find out the other party’s areas of interest and then to read up furiously on the relevant subjects so that you can regurgitate everything during your conservations. Being artistic isn’t about memorising all the names of famous artists and masterpieces without being able to be sincerely moved by the ingenuity and emotions that went into the creative processes involved in crafting these works. Being caring isn’t about being chivalrous, and neither is being polite about dining in a certain fashion. Being confident isn’t about employing your diaphragm when speaking, or about moving in a deliberately slow and smooth motion. Being attractive isn’t about following hard-and-fast rules. Falling in love isn’t about losing your own individuality; it is about being accepted for who you are, it is about being a better person for your partner. (Yes, I sound so clichéd, I know.)

If you think I make more sense than Dr Philanderer, then just keep these in mind: 1) Extend your efforts to be brilliant to every single part of your life, such that you eventually internalise all these amazing qualities, such that they naturally come to form your character; and 2) don’t try too hard to impress, because it is revolting.”

I consider myself exceedingly lucky to have met and become a friend of the author of the words above, and I consider it highly unlikely that this is the last quote I’ll post from that site.

June 6, 2012 Posted by | dating, quotes/aphorisms | 1 Comment

Wikipedia articles of interest

i. Song Dynasty. [featured, great article with lots of links)

“The Song Dynasty (Chinese: 宋朝; pinyin: Sòng Cháo; Wade-Giles: Sung Ch’ao; IPA: [sʊ̂ŋ tʂʰɑ̌ʊ̯]) was a ruling dynasty in China between 960 and 1279; it succeeded the Five Dynasties and Ten Kingdoms Period, and was followed by the Yuan Dynasty. It was the first government in world history to issue banknotes or paper money, and the first Chinese government to establish a permanent standing navy. This dynasty also saw the first known use of gunpowder, as well as first discernment of true north using a compass. […]

The population of China doubled in size during the 10th and 11th centuries. This growth came through expanded rice cultivation in central and southern China, the use of early-ripening rice from southeast and southern Asia, and the production of abundant food surpluses.[4][5] […]

The Song Dynasty was an era of administrative sophistication and complex social organization. Some of the largest cities in the world were found in China during this period (Kaifeng and Hangzhou had populations of over a million).[1][48] People enjoyed various social clubs and entertainment in the cities, and there were many schools and temples to provide the people with education and religious services.[1] The Song government supported multiple forms of social welfare programs, including the establishment of retirement homes, public clinics, and pauper‘s graveyards.[1] The Song Dynasty supported a widespread postal service that was modeled on the earlier Han Dynasty (202 BC – AD 220) postal system to provide swift communication throughout the empire.[49] The central government employed thousands of postal workers of various ranks and responsibilities to provide service for post offices and larger postal stations.[50] […]

The Song military was chiefly organized to ensure that the army could not threaten Imperial control, often at the expense of effectiveness in war. Northern Song’s Military Council operated under a Chancellor, who had no control over the imperial army. The imperial army was divided among three marshals, each independently responsible to the Emperor. Since the Emperor rarely led campaigns personally, Song forces lacked unity of command.[89] The imperial court often believed that successful generals endangered royal authority, and relieved or even executed them (notably Li Gang,[90] Yue Fei, and Han Shizhong.[91])

Although the scholar-officials viewed military soldiers as lower members in the hierarchic social order,[92] a person could gain status and prestige in society by becoming a high ranking military officer with a record of victorious battles.[93] At its height, the Song military had one million soldiers[22] divided into platoons of 50 troops, companies made of two platoons, and one battalion composed of 500 soldiers.[94][95] Crossbowmen were separated from the regular infantry and placed in their own units as they were prized combatants, providing effective missile fire against cavalry charges.[95] The government was eager to sponsor new crossbow designs that could shoot at longer ranges, while crossbowmen were also valuable when employed as long-range snipers.[96] Song cavalry employed a slew of different weapons, including halberds, swords, bows, spears, and ‘fire lances‘ that discharged a gunpowder blast of flame and shrapnel.[97]

Military strategy and military training were treated as science that could be studied and perfected; soldiers were tested in their skills of using weaponry and in their athletic ability.[98] The troops were trained to follow signal standards to advance at the waving of banners and to halt at the sound of bells and drums.[95] […]

The economy of the Song Dynasty was one of the most prosperous and advanced economies in the medieval world. […] The Song economy was stable enough to produce over a hundred million kilograms (over two hundred million pounds) of iron product a year.[133] […] The annual output of minted copper currency in 1085 alone reached roughly six billion coins.[4] The most notable advancement in the Song economy was the establishment of the world’s first government issued paper-printed money, known as Jiaozi […] The size of the workforce employed in paper money factories was large; it was recorded in 1175 that the factory at Hangzhou employed more than a thousand workers a day.[135] […]

The innovation of movable type printing was made by the artisan Bi Sheng (990–1051), first described by the scientist and statesman Shen Kuo in his Dream Pool Essays of 1088.[179][180] The collection of Bi Sheng’s original clay-fired typeface was passed on to one of Shen Kuo’s nephews, and was carefully preserved.[180][181] Movable type enhanced the already widespread use of woodblock methods of printing thousands of documents and volumes of written literature, consumed eagerly by an increasingly literate public. The advancement of printing had a deep impact on education and the scholar-official class, since more books could be made faster while mass-produced, printed books were cheaper in comparison to laborious handwritten copies.[67][71] The enhancement of widespread printing and print culture in the Song period was thus a direct catalyst in the rise of social mobility and expansion of the educated class of scholar elites, the latter which expanded dramatically in size from the 11th to 13th centuries.[67][182]

ii. Tidal flexing.

“Tidal acceleration is an effect of the tidal forces between an orbiting natural satellite (e.g. the Moon), and the primary planet that it orbits (e.g. the Earth). The acceleration is usually negative, as it causes a gradual slowing and recession of a satellite in a prograde orbit away from the primary, and a corresponding slowdown of the primary’s rotation. The process eventually leads to tidal locking of first the smaller, and later the larger body. The Earth-Moon system is the best studied case.

The similar process of tidal deceleration occurs for satellites that have an orbital period that is shorter than the primary’s rotational period, or that orbit in a retrograde direction. […]

Because the Moon‘s mass is a considerable fraction of that of the Earth (about 1:81), the two bodies can be regarded as a double planet system, rather than as a planet with a satellite. The plane of the Moon’s orbit around the Earth lies close to the plane of the Earth’s orbit around the Sun (the ecliptic), rather than in the plane perpendicular to the axis of rotation of the Earth (the equator) as is usually the case with planetary satellites. The mass of the Moon is sufficiently large, and it is sufficiently close, to raise tides in the matter of the Earth. In particular, the water of the oceans bulges out along both ends of an axis passing through the centers of the Earth and Moon. The average tidal bulge closely follows the Moon in its orbit, and the Earth rotates under this tidal bulge in just over a day. However, the rotation drags the position of the tidal bulge ahead of the position directly under the Moon. As a consequence, there exists a substantial amount of mass in the bulge that is offset from the line through the centers of the Earth and Moon. Because of this offset, a portion of the gravitational pull between Earth’s tidal bulges and the Moon is perpendicular to the Earth-Moon line, i.e. there exists a torque between the Earth and the Moon. This boosts the Moon in its orbit, and decelerates the rotation of the Earth.

As a result of this process, the mean solar day, which is nominally 86400 seconds long, is actually getting longer when measured in SI seconds with stable atomic clocks. (The SI second, when adopted, was already a little shorter than the current value of the second of mean solar time.[9]) The small difference accumulates every day, which leads to an increasing difference between our clock time (Universal Time) on the one hand, and Atomic Time and Ephemeris Time on the other hand: see ΔT. This makes it necessary to insert a leap second at irregular intervals. […]

Tidal acceleration is one of the few examples in the dynamics of the Solar System of a so-called secular perturbation of an orbit, i.e. a perturbation that continuously increases with time and is not periodic. Up to a high order of approximation, mutual gravitational perturbations between major or minor planets only cause periodic variations in their orbits, that is, parameters oscillate between maximum and minimum values. The tidal effect gives rise to a quadratic term in the equations, which leads to unbounded growth. In the mathematical theories of the planetary orbits that form the basis of ephemerides, quadratic and higher order secular terms do occur, but these are mostly Taylor expansions of very long time periodic terms. The reason that tidal effects are different is that unlike distant gravitational perturbations, friction is an essential part of tidal acceleration, and leads to permanent loss of energy from the dynamical system in the form of heat.”

iii. Error function. Somewhat technical, but interesting (the article has a lot more):

“In mathematics, the error function (also called the Gauss error function) is a special function (non-elementary) of sigmoid shape which occurs in probability, statistics and partial differential equations. It is defined as:[1][2]

\operatorname{erf}(x) = \frac{2}{\sqrt{\pi}}\int_{0}^x e^{-t^2} dt.

(When x is negative, the integral is interpreted as the negative of the integral from x to zero.) […]

The error function is used in measurement theory (using probability and statistics), and although its use in other branches of mathematics has nothing to do with the characterization of measurement errors, the name has stuck.

The error function is related to the cumulative distribution \Phi, the integral of the standard normal distribution (the “bell curve”), by[2]

\Phi (x) = \frac{1}{2}+ \frac{1}{2} \operatorname{erf} \left(x/ \sqrt{2}\right)

The error function, evaluated at  \frac{x}{\sigma \sqrt{2}}  for positive x values, gives the probability that a measurement, under the influence of normally distributed errors with standard deviation \sigma, has a distance less than x from the mean value.[3] This function is used in statistics to predict behavior of any sample with respect to the population mean. This usage is similar to the Q-function, which in fact can be written in terms of the error function.”

iv. Lake Vostok

Lake Vostok (Russian: озеро Восток, lit. “Lake East”) is the largest of more than 140 sub-glacial lakes and was recently drilled into by Russian scientists. The overlying ice provides a continuous paleoclimatic record of 400,000 years, although the lake water itself may have been isolated for 15[3][4] to 25 million years.[5]

Lake Vostok is located at the southern Pole of Cold, beneath Russia‘s Vostok Station under the surface of the central East Antarctic Ice Sheet, which is at 3,488 metres (11,444 ft) above mean sea level. The surface of this fresh water lake is approximately 4,000 m (13,100 ft) under the surface of the ice, which places it at approximately 500 m (1,600 ft) below sea level. Measuring 250 km (160 mi) long by 50 km (30 mi) wide at its widest point, and covering an area of 15,690 km2 (6,060 sq mi), it is similar in area to Lake Ontario, but with over three times the volume. The average depth is 344 m (1,129 ft). It has an estimated volume of 5,400 km3 (1,300 cu mi).[2] The lake is divided into two deep basins by a ridge. The liquid water over the ridge is about 200 m (700 ft), compared to roughly 400 m (1,300 ft) deep in the northern basin and 800 m (2,600 ft) deep in the southern. […]

The coldest temperature ever observed on Earth, −89 °C (−128 °F), was recorded at Vostok Station on 21 July 1983.[3] The average water temperature is calculated to be around −3 °C (27 °F); it remains liquid below the normal freezing point because of high pressure from the weight of the ice above it.[30] Geothermal heat from the Earth’s interior may warm the bottom of the lake.[31][32][33] The ice sheet itself insulates the lake from cold temperatures on the surface. […]

The lake is under complete darkness, under 350 atmospheres (5143 psi) of pressure and expected to be rich in oxygen, so there is speculation that any organisms inhabiting the lake could have evolved in a manner unique to this environment.[19][36] These adaptations to an oxygen-rich environment might include high concentrations of protective oxidative enzymes.

Living Hydrogenophilus thermoluteolus micro-organisms have been found in Lake Vostok’s deep ice core drillings; they are an extant surface-dwelling species.[35][40] This suggests the presence of a deep biosphere utilizing a geothermal system of the bedrock encircling the subglacial lake. There is optimism that microbial life in the lake may be possible despite high pressure, constant cold, low nutrient input, potentially high oxygen concentration and an absence of sunlight.[35][41][42]

Jupiter‘s moon Europa and Saturn‘s moon Enceladus may also harbor lakes or oceans below a thick crust of ice. Any confirmation of life in Lake Vostok could strengthen the prospect for the presence of life on icy moons.[35][43]

v. Nicosia

Nicosia (/ˌnɪkəˈsə/ NIK-ə-SEE), known locally as Lefkosia (Greek: Λευκωσία, Turkish: Lefkoşa), is the capital and largest city in Cyprus, as well as its main business center.[2] After the collapse of the Berlin Wall, Nicosia remained the only divided capital in the world,[3] with the southern and the northern portions divided by a Green Line.[4] It is located near the center of the island, on the banks of the Pedieos River.

Nicosia is the capital and seat of government of the Republic of Cyprus. The northern part of the city functions as the capital of the self-proclaimed Turkish Republic of Northern Cyprus, a disputed breakaway region whose independence is recognized only by Turkey, and which the rest of the international community considers as occupied territory of the Republic of Cyprus since the Turkish Invasionin 1974. […]

The Turkish invasion, the continuous occupation of Cyprus as well as the self-declaration of independence of the TRNC have been condemned by several United Nations Resolutions adopted by the General Assembly and the Security Council. The Security Council is reaffirming their condemnation every year.[40]

vi. Perennial plant

“A perennial plant or simply perennial (Latin per, “through”, annus, “year”) is a plant that lives for more than two years.[1] The term is often used to differentiate a plant from shorter lived annuals and biennials. The term is sometimes misused by commercial gardeners or horticulturalists to describe only herbaceous perennials. More correctly, woody plants like shrubs and trees are also perennials.

Perennials, especially small flowering plants, grow and bloom over the spring and summer and then die back every autumn and winter, then return in the spring from their root-stock, in addition to seeding themselves as an annual plant does. These are known as herbaceous perennials. However, depending on the rigors of local climate, a plant that is a perennial in its native habitat, or in a milder garden, may be treated by a gardener as an annual and planted out every year, from seed, from cuttings or from divisions. […]

Although most of humanity is fed by seeds from annual grain crops, perennial crops provide numerous benefits.[3] Perennial plants often have deep, extensive root systems which can hold soil to prevent erosion, capture dissolved nitrogen before it can contaminate ground and surface water, and outcompete weeds (reducing the need for herbicides). These potential benefits of perennials have resulted in new attempts to increase the seed yield of perennial species,[4] which could result in the creation of new perennial grain crops.[5] Some examples of new perennial crops being developed are perennial rice and intermediate wheatgrass.”

vii. Anaconda Plan.

“The Anaconda Plan or Scott’s Great Snake is the name widely applied to an outline strategy for subduing the seceding states in the American Civil War. Proposed by General-in-Chief Winfield Scott, the plan emphasized the blockade of the Southern ports, and called for an advance down the Mississippi River to cut the South in two. Because the blockade would be rather passive, it was widely derided by the vociferous faction who wanted a more vigorous prosecution of the war, and who likened it to the coils of an anaconda suffocating its victim. The snake image caught on, giving the proposal its popular name.”

viii. Caesar cipher (featured).

“In cryptography, a Caesar cipher, also known as Caesar’s cipher, the shift cipher, Caesar’s code or Caesar shift, is one of the simplest and most widely known encryption techniques. It is a type of substitution cipher in which each letter in the plaintext is replaced by a letter some fixed number of positions down the alphabet. For example, with a shift of 3, A would be replaced by D, B would become E, and so on. The method is named after Julius Caesar, who used it in his private correspondence.

The encryption step performed by a Caesar cipher is often incorporated as part of more complex schemes, such as the Vigenère cipher, and still has modern application in the ROT13 system. As with all single alphabet substitution ciphers, the Caesar cipher is easily broken and in modern practice offers essentially no communication security.”

If you don’t really know much about cryptography but would like a quick and accessible introduction to the subject matter, I recommend Brit Cruise’ videos on the subject at Khan Academy.

ix. Water purification. From the article:

“It is not possible to tell whether water is of an appropriate quality by visual examination. Simple procedures such as boiling or the use of a household activated carbon filter are not sufficient for treating all the possible contaminants that may be present in water from an unknown source. Even natural spring water – considered safe for all practical purposes in the 19th century – must now be tested before determining what kind of treatment, if any, is needed. Chemical and microbiological analysis, while expensive, are the only way to obtain the information necessary for deciding on the appropriate method of purification.

According to a 2007 World Health Organization (WHO) report, 1.1 billion people lack access to an improved drinking water supply, 88 percent of the 4 billion annual cases of diarrheal disease are attributed to unsafe water and inadequate sanitation and hygiene, and 1.8 million people die from diarrheal diseases each year. The WHO estimates that 94 percent of these diarrheal cases are preventable through modifications to the environment, including access to safe water.[1] Simple techniques for treating water at home, such as chlorination, filters, and solar disinfection, and storing it in safe containers could save a huge number of lives each year.[2] Reducing deaths from waterborne diseases is a major public health goal in developing countries.”

Here’s a related paper on ‘Global Distribution of Outbreaks of Water-Associated Infectious Diseases‘ which I’ve previously blogged here.

June 6, 2012 Posted by | astronomy, biology, Cryptography, Geography, health, history, mathematics, medicine, Physics, wikipedia | Leave a comment