Monday, February 23, 2009

That dreaded IQ again

I am continually amazed at people's capacity to fool themselves. And the smarter you are, the better you are at fooling yourself, it seems. Perhaps the most persistent fallacious belief is that there is such a thing as "healthy" food. Many people, particularly well-educated people, desperately want to believe that they can extend their lifespan by controlling what goes into their mouths. And what is the usual definition of "healthy" food? Low-fat food. And you cannot pick up a newspaper or magazine without seeing some comment about healthy food. Yet there is, as far as I am aware, no such thing. As you can see in the sidebar of my FOOD & HEALTH SKEPTIC blog, the biggest, best and most conclusive research study of the subject found that a low-fat diet had no effect on your health whatever! But that finding was like water off a duck's back. Although the U.S. government spent $400 million on making the study the very best piece of research that could be conducted on the subject, I have yet to see a single mention of it in the popular press and middle-class people still fuss about their food as if it will do them some long-term good. It is a form of religion I guess. People just NEED to feel that they have some control over their fate.

And people's understanding of IQ also seems to be needs-driven. Just about the worst thing you can be called in the USA today is a "racist", yet IQ tests clearly show that blacks are, on average, outstandingly dumb. And their high level of dysfunctional behaviour and low level of educational and economic success is exactly what you would expect of dumb people. It is clear that the tests do not lie. Prisons are full of dumb people and huge numbers of them are black.

But what I have just said is for most people very threatening. If they accept its obvious truth, they risk being seen both by themselves and others as "racist", and that will not do at all. So there are all sorts of mental wriggles that people use to avoid accepting what I have just said. And the truth of all those wriggles has of course been extensively tested and found to be lacking. But there are whole books written on that subject (start here if you want to look into it) so I will not go into details now about it.

What started me off on that little meditation was something very simple, the strapline (subheading) given for the article excerpted below. In answer to the question "Why men are more intelligent than women", the strapline gives an answer: "They aren't". Yet that strapline does not represent the findings reported in the article at all. The article is a generally accurate summary of our current knowledge about IQ and says that women DO on average have slightly lower IQs. It then makes a start on explaining why.

So why such an inaccurate strapline? Because the article was published in a semi-popular magazine and there would have been great cries of outrage from both feminists and real women otherwise. The fact that averages tell us nothing about any one individual within a given population would be no consolation. Many women would just not WANT to believe the conclusion so they had to be assuaged. So the conclusions were slanted to deflect attention from the actual averages to theoretical averages.
Why men are more intelligent than women

The answer is: They aren't.

By Satoshi Kanazawa

The orthodoxy in intelligence research for the second half of the 20th century had been that men and women had the same average intelligence, but men had greater variance in their distribution than women. Most geniuses were men, and most imbeciles were men, they said, while most women were in the normal range. This conclusion, however, was manufactured out of political expediency. Not wanting to discover, or a priori denying, any sex differences in intelligence, psychometricians simply deleted from the standardized IQ tests any item on which the performance of men and women differed.

More recently, however, especially since the turn of the millennium, there have been an increasing number of studies that cast doubt on this politically correct conclusion. Studies with large representative national samples from Spain, Denmark, and the United States, as well as meta-analyses of a large number of published studies throughout the world, all conclude that men on average are slightly but significantly more intelligent than women, by about 3-5 IQ points. So this has now become the new (albeit tentative) consensus in intelligence research.

However, these studies do not answer the ultimate evolutionary question of why men should be more intelligent than women. General intelligence likely evolved as a domain-specific psychological mechanism to deal with evolutionary novelty. However, unlike populations in different geographic parts of the world [translation: different races], men and women within a population have always faced the same level of evolutionary novelty throughout evolutionary history, because they have always migrated together. If general intelligence is a function of the evolutionary novelty of the environment, why then are men on average slightly more intelligent than women? My LSE colleague, Diane J. Reyniers, and I offer one possible explanation in our article, forthcoming in the American Journal of Psychology.

Psychometricians have known since the end of the 19th century that height is positively correlated with intelligence: Taller people on average are more intelligent than shorter people. And men in every human population are taller than women. So one possibility is that men are more intelligent than women, not because they are men, but because they are taller.....

More here

I am not sure why Kanazawa claims that items differentiating men and women have been excluded from IQ tests in the past. It is demonstrably and grossly untrue. He must have in mind some particular instance that is well outside normal practice. It is demonstrably untrue because many items in standard IQ tests DO discriminate men and women. For instance, women tend to do better on verbal puzzles and men do better on mathematical puzzles.

Normal psychometric practice is to select test items by the extent to which they hang together (correlate) with other items -- using such criteria as factor loadings or item-to-total correlations. Doing anything else would damage both the reliability and validity of the test.

It has been suggested -- correctly -- that one could construct an IQ test that did not discriminate men and women by adding in more verbal items and deleting some mathematical items but since the difference between men and women is small, it is hard to see what would be gained by that and, as mentioned, it would detract from at least the validity (construct validity, to be technical) of the test and probably the reliability also.

It would be nice to think that one could dictate the final composition of an IQ test or any other test by the initial item pool that one starts out with before test construction begins but that is not wholly true if one is really doing research rather than just making things up. I have found, for instance, that a subset of items that are not strongly represented in the initial item pool can be quite dominant in the test which emerges from the item analyses. See here for instance. So reality tends to defy intentions and expectations. In other words, there is every reason to believe that existing IQ tests give a correctly balanced picture of IQ. What is in them has emerged empirically.

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ELSEWHERE

The self-defeating stimulus: "[Nobel Prize-winning economist Edmund] Phelps is among the world's leading authorities on the way different economic systems enable or thwart the dynamic adjustment and entrepreneurial innovation that delivers long-run productivity and growth. By significantly increasing government involvement in so many sectors of the economy, Phelps worries the enacted stimulus plan could make the climate of investment more rather than less uncertain, and make growth-enhancing innovation less rather than more likely. Potential investors may become spooked by businesses increasingly dependent on government contracts, Phelps notes, since these firms may face additional regulations and bureaucratic requirements which may make them appear less able nimbly to adapt. Additionally, the anticipation of higher future taxes - the price of the current spending surge - could dampen consumer demand and `have a chilling effect upon the desire of entrepreneurs to innovate,' Phelps says."

Public "servants": "We are constantly urged to admire the 'sacrifice' of `public servants,' and to revile the `greed' and 'selfishness' of those who choose to make an honest living in the private sphere. Yet public 'service' is frequently a much more lucrative racket than honest private work. Witness the fact, reported in a Washington Post column by Chris Edwards in August 2006, that the average federal civilian employee is paid twice the amount that was earned by the average private sector worker - a little more than $106,000 per year, as compared to an annual salary of $56,000. Note as well that while real estate prices are plummeting throughout most of the country, the suburbs and exurbs of the Imperial Capital continue to boom, thanks in no small measure to the metastatic growth of government and the lucrative compensation enjoyed by the federal nomenklatura."

Yesterday's history is today's politics (Comment from Britain): "The Petrograd Strikes, which heralded the start of the 1917 Revolution in Russia commenced on 22 February; find a moment for reflection this Sunday. Even though the Soviet system of Communism lasted for 69 years, its ideology is evidently still very much alive and well: the British government now spends half the nation's income. Yesterday's history is today's politics, to adapt the adage. This Thursday our very own Nicholas II went to see the Pope. Perhaps he asked the Vicar of Christ to pray for a miracle - huge monetary expansion without hyperinflation - or perhaps he asked for the economy to receive the Last Rites. Ironically, one of the things the Prime Minister did discuss was freeing the world from poverty. He can contribute best to this desirable goal in Great Britain by the near abolishment of the State."

Taxpayers treated to an education recently : "Our education in government affairs, politicians and such continued over the past few weeks. We learned, for instance, that a fair number of politicians owe a fair amount of taxes that they hadn't given a thought to, until, of course, they were considered for a Cabinet post. But average taxpayers like you and I were expected to understand that these were busy people leading big, important lives, who had fingers in many pies, and that these were all `honest' and `unintentional' mistakes. We also learned that in a 300-million-plus country, there is sometimes just one person with the right knowledge, skills and experience for a particular job, and when such a person comes along, we were expected to cut him some slack and not fuss over things like his taxes. Several things have been bothering me lately. One of them is the arbitrariness of it all. . Just what are the rules, and who gets to make them?"

There is a new lot of postings by Chris Brand just up -- on his usual vastly "incorrect" themes of race, genes, IQ etc.

For more postings from me, see TONGUE-TIED, EDUCATION WATCH INTERNATIONAL, GREENIE WATCH, POLITICAL CORRECTNESS WATCH, GUN WATCH, SOCIALIZED MEDICINE, FOOD & HEALTH SKEPTIC, AUSTRALIAN POLITICS, IMMIGRATION WATCH INTERNATIONAL, EYE ON BRITAIN and Paralipomena

List of backup or "mirror" sites here or here -- for readers in China or for everyone when blogspot is "down" or failing to update. Email me here (Hotmail address). My Home Pages are here or here or here

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The Big Lie of the late 20th century was that Nazism was Rightist. It was in fact typical of the Leftism of its day. It was only to the Right of Stalin's Communism. The very word "Nazi" is a German abbreviation for "National Socialist" (Nationalsozialist) and the full name of Hitler's political party (translated) was "The National Socialist German Workers' Party" (In German: Nationalsozialistische Deutsche Arbeiterpartei)

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