Econstudentlog

Random wikipedia links of interest

1. Corrosion.

2. Demographics of the People’s Republic of China. A few quotes from the article:

a) “Census data obtained in 2000 revealed that 119 boys were born for every 100 girls, and among China’s “floating population” the ratio was as high as 128:100. These situations led the government in July 2004 to ban selective abortions of female fetuses. It is estimated that this imbalance will rise until 2025–2030 to reach 20% then slowly decrease.[2]”

b) “Average household size (2005) 3.1; rural households 3.3; urban households 3.0.
Average annual per capita disposable income of household (2005): rural households Y 3,255 (U.S.$397), urban households Y 10,493 (U.S.$1,281).”

c) A map of the population density (darker squares have higher density):

The ‘average population density’ of 137/km2 is not an all that interesting variable. The Gobi desert is not a nice place for humans to live: The temperature variation in the area is extreme, ranging from –40°C in the winter to +50°C in the summer.

3. Cost overrun. An excerpt:

“Cost overrun is common in infrastructure, building, and technology projects. One of the most comprehensive studies [1] of cost overrun that exists found that 9 out of 10 projects had overrun, overruns of 50 to 100 percent were common, overrun was found in each of 20 nations and five continents covered by the study, and overrun had been constant for the 70 years for which data were available. For IT projects, an industry study by the Standish Group (2004) found that average cost overrun was 43 percent, 71 percent of projects were over budget, over time, and under scope, and total waste was estimated at US$55 billion per year in the US alone.”

4. Tensor. This is difficult stuff.

5. Eye.

June 16, 2010 - Posted by | biology, Chemistry, data, demographics, economics, Geography, mathematics, wikipedia

7 Comments »

  1. Kudos for the links. I am a Wikipedia fan myself, and often spend a full day there, wandering from link to link.

    One thing about the Chinese demographics: always keep in mind that the bulk of these data are supplied by the Chinese government, and thus treat them with a shipload of salt. E.g. (from the same article):

    1) Annual reported arrest rate per 100,000 population (2006) for:
    …..
    * Endangering public security: 1.010

    (Plamus’ comment: how does this comport with the reports of 70,000 or so public disorder (meaning: riot) accidents a year, some of which involve thousands of people battling the police?)

    2) Quality of working life:
    * Average workweek: 40 hours (1998)
    * Annual rate per 100,000 workers for: (1997)
    o injury or accident: 0.7
    o industrial illness: 36
    o death: 1.4

    (Plamus’ comment: 40 hours/week, eh? How convenient! No one ever works overtime on an urgent project, and every peasant is employed for 40 hours/week in the winter – or those two (and many others) perfectly cancel each other out to net the government-prescribed 40-hour workweek. Gotta love neat round numbers. And that injury rate of 0.7 per 100,000? Works out to about 100,000 deaths overall – yet (also from Wikipedia) “China, in particular, has the highest number of coal mining related deaths in the world, with official statistic 6,027 deaths in 2004.” This is just from one sub-sector (coal mining) of one industry (mining). At the same time “industrial illness” runs at 36 per 100,000. I cannot help but suspect they quite often treat injury as industrial illness.)

    As Dzerzhinsky was fond of saying, trust but verify… or at least use a healthy dose of skepticism when governments tell you that everything is hunky-dory.

    As an aside: extra kudos for your comment to Alex Tabarrok’s post on MR. Americans so often fail to realize that they did not defeat Hitler – the Russians did. Alternatively, the preoccupation with Hitler often prevents the rest of the world from appreciating how hard containing Japan would have been if it had not been for the Americans – and yes, that includes the much-maligned nukes over Hiroshima and Nagasaki. But that’s a topic for a discussion that would be a thread hijack that I will not go for, unless our kind host wants to welcome it.

    All the best!

    Comment by Plamus | June 17, 2010 | Reply

  2. Hi Plamus

    always keep in mind that the bulk of these data are supplied by the Chinese government, and thus treat them with a shipload of salt.

    Oh, I do. Just as I keep in mind constantly that literally everybody with an internet connection can edit a wikipedia article.

    That’s actually the main reason why I didn’t comment further on any numbers in that article; I don’t know enough to know much about what to make of them – but I was pretty sure that the income of the urban areas are much higher than that of the rural areas and that the gender imbalance is huge, so I didn’t see any problem in reporting those numbers.

    As soon as we’re dealing with anything but data of first world countries, I usually get very skeptical about the official data supplied. China is a country where people are still being executed for openly speaking out against the regime (don’t even ask what they do with the bodies) and it’s still run by CPC, a former leader of which is by far the greatest (is that the word you use? Or is it largest or perhaps biggest?) mass murderer the world has ever seen. So, yeah, it’s not like I’m a big fan of the regime or that I trust them all that much.

    I also btw. think China has a relatively high amount of cancer cases which are more or less directly linked to production, something the article completely neglects to mention in the relevant section (their factories poisons local populations in the surrounding areas, people who later die of cancer).

    Regarding Japan, you’ll not hear me argue that Japan wasn’t a tough country to break nor that it wasn’t mainly the US that did it. This book (the title of the book means: ‘The Second World War’, in Danish, 668 pages), which I read in August 08 – I wrote a Danish post about the book here, I didn’t recommend it), had quite a bit about the war in the Pacific, and it’s only maybe a month ago that I watched (most of) the World at War series (if you don’t know, google it, I recommend it). So I’ve previously read about the war in the Pacific in general as well as the Japanese occupation of Manchuria (or Manchukuo) in particular, where people were gassed and subjected to biological warfare, forced labor ect. by the Imperial Japanese Army, or more specifically the Kwantung Army, long before World War 2 proper had even begun. Japan was at war more or less constantly from 1931 to 1945, something I believe only relatively few Europeans are aware of. She was a formidable foe which at the height of her power controlled almost 7,5 million square kilometres, almost 3/4th of the area of Europe.

    After I read the articles about Operation Crossroads, I’ve seen the nukes used on Japan in a somewhat different light, however not all that different. People taking the decision back then simply didn’t know much, if anything, about the long term effects on the environment, cancer risks, ect., ect. – people tend to forget these things today and/or let current knowledge influence their evaluation of decisionmaking back then – which is both natural yet also quite problematic. Back when the decision was made, it was a huge new weapon, a bomb that would kill a lot of people, scare the Russians and hopefully end the war fast. It worked. I won’t ever know if I would have made the same decision if it was up to me – I wasn’t born, I wasn’t there.

    In other words, your ‘thread hijack’ is welcome.

    Comment by US | June 17, 2010 | Reply

  3. Thanks for welcoming my brutal hijacking, US.

    My cable provider carries the Military Channel, which runs the World at War series almost every day – so I have seen most, if not all of it, and I second your recommendation.

    Regarding Mao: hmm, good question, I suppose we could agree on “most prolific” murderer of all times. Reading about The Great Leap Forward is a blood-curdling exercise. Endless topic in itself.

    Regarding Operation Crossroads: I agree that using nukes was a decision made with imperfect (in fact, seriously deficient) information. But it was not made without any information. It was known and expected that a nuclear blast would mostly decommission a city, and would kill a significant portion of its inhabitants – although whether 30%, 60%, or 90% was not known. Thus, however, some idea of the upper limit of casualties was available – the full population of the city and its immediate vicinity. It was also known what kind of resistance the Japanese military had put up defending strategically and tactically insignificant islands in the Pacific – and thus the extrapolated (yes, I know, bad – but you use them when it’s all you have!) estimates from an invasion of the Japanese mainland began in the millions on the Japanese side, and the high hundreds of thousands on the American side. The spirit of a Bushido death wish had gripped Japan. Firebombing Tokyo had not brought any indication that the Japanese government was considering capitulation – in fact, their propaganda urging the civilian populace to fight the invaders on the beaches had intensified. I guess what I find very frustrating is that most people do not have your educated ambivalence, but rather ignorant eagerness to judge ex post facto. It does not even occur to them that the use of nuclear weapons, while tragic for the people from Hiroshima and Nagasaki, may have meant fewer casualties overall by an order of magnitude. It’s a horrible, monstrous arithmetic, but one has to be willing to engage in it if one is going to pass judgment. One’s counterfactual cannot be “well, if nukes had not been used, and the Japanese government had miraculously decided to surrender…”; it has to consider “if nukes had not been used, and full-bore invasion had been undertaken…” You know, the kind of scenario when every major city is firebombed (coupled with Japanese wood-and-paper architecture), the beaches are chewed up by heavy naval artillery, and machine gun nests mow down waves of attacking civilians – who were sharpening bamboo spears at the urging of the government…

    Like you, I cannot say I would have made the same decision – but I can say I would not have ruled it out.

    Comment by Plamus | June 18, 2010 | Reply

  4. @Plamus

    Regarding the nukes, the main new thing I learned from reading about Operation Crossroads was that the long term effects of nuclear blasts were most certainly almost completely unknown to the decisionmakers at the time of the bombings of Hiroshima and Nagasaki. They’d never have conducted the Baker test the way they did if they had known more about these things, and the Baker test was in fact one of the main data points that made people realize how much long run environmental ect. damage nuclear bombs can cause. Of course it wasn’t a surprise that the bombs would kill a lot of people – that was kind of the whole point; but I’m pretty sure people like Truman didn’t know that there would still be Japanese people living in the areas today, 65 years later, that would get cancer or be infertile because of the decision to bomb the cities back then. Yet this is something people draw into this discussion too when evaluating the decision made, and I don’t think that’s completely fair to the decisionmakers – there was a lot of stuff that would later pop up that they just didn’t know at the time where the decisions were made. That doesn’t completely exculpate them of course, but it should in my mind make us evaluate their decisions a little differently. And as you say, the realistic alternatives would have to be analyzed in detail as well before passing judgment.

    Comment by US | June 18, 2010 | Reply

  5. Again (shocker!) we are in almost complete agreement. Does that say something about rational people discussing issues – and not even at the same table, with ample alcohol (my preferred mode of operation)?

    All the best!

    Comment by Plamus | June 21, 2010 | Reply

  6. You too.

    I don’t have much experience discussing issues with other people offline under the influence of alcohol, so I can’t comment much on the difference between doing that and discussing things here.

    As it is, I don’t know if our agreement here tells us all that much: We both formed our opinions in quite a bit of detail before this exchange took place, and we formed our opinions based on a lot of (/similar/the same) information. Were you thinking along the lines of Aumann’s agreement theorem when posing the question? I must admit I still don’t quite know exactly what to make of that.

    Comment by US | June 21, 2010 | Reply

  7. Yes, I had Aumann’s in mind. We found out each other’s priors, and they turned out to be close enough, if not identical. We are intelligent enough to be Bayesians when it’s warranted. We made our posteriors common knowledge. Ergo, it’s not surprising that we agree, i.e. our posteriors are close.

    Now that I think about it, social setting (table, alcohol, etc.) may be conducive to more common priors, but is not necessarily so. On the other hand, it does significantly decrease the amount of research and forethought invested in an ongoing discussion, i.e. may make one a worse Bayesian. I may need to start to drink more at home [chuckle].

    Comment by Plamus | June 22, 2010 | Reply


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