Sunday, November 25, 2007

But don't take my word for it

You don't have to believe me that the evidence supporting the hypothesis that intelligence is primarily genetic is weak. James R. Flynn of Flynn effect fame thinks so too.

5 comments:

denis bider said...

Same old, same old.

Flynn is one of those people who helped identify something new and fundamental, and then go on living their lives denying the best explanation because they would like it to be different.

The Flynn effect is best explained by heterosis, which simultaneously explains phenomena such as why people have gotten taller in the past century, and why this growth has been most pronounced in cities. The argument Flynn makes instead - and the basketball parallel - is wishful thinking, which Mingroni debunks thoroughly in his paper.

I'm not sure why you're insisting on beating this dead horse. I've long since accepted that you won't be converted to the rational outlook. You are a believer; your spiritual well-being rests on whether a certain hypothesis is right. You are not alone in this respect. Many researchers commit the same error of letting their inquiries be directed by wishful thinking. People form a hypothesis based on what they would like reality to be; not based on what the naked facts tell them; and so they spend decades trying to find out that group selection for lower populations would favor individual restraint in breeding, only to eventually find out that group selection for lower populations leads to cannibalism victimizing especially young females.

Stop trying to persuade everyone how unbiased you are, when everything you write clearly shows that, while you are rational for the most part, you clearly have a weakness for people you perceive as victims, and will side with them whatever the debate. Under such circumstance, any communication that we undertake is not a dialogue, but more so a battle between a "valiant knight" and an "attacker", disguised as a rational argument.

In the short run, battles are amusing, but in the long run, they provide only diminishing returns.

denis bider said...

I understand how, in the absence of a god - or a Flying Spaghetti Monster willing to exercise its holy noodly appendage - it would be extremely convenient if all the ills of the world - all the reasons for various people's suffering - could somehow be traced back to something or other caused by the Rich White Male. In the absence of a god, or a Flying Spaghetti Monster, the Rich White Male is, at least until the Chinese rise, the closest to a deity that we can get. So it would be great if we can blame all sorts of problems on the Rich White Male, because if these problems are caused by Him, then surely He can fix them. Or else, exploiting the fact that He is not an all-powerful deity after all, perhaps he might be forced to fix them.

But just because it would be most expedient if the Rich White Male could be coaxed to fix all number of things, does not mean that the Rich White Male is the one who made those problems. Even more importantly, it doesn't mean that he has the power to fix them.

Communists tried this; they tried to do away with simple and effective market rules, which in the short run hurt the weakest, but in the long run elevate all; and they replaced those rules with a command economy, which in the short run benefitted everybody, all the mine workers got a 2x raise, but when after 7 days the furnaces broke down and there were no engineers left to fix them, the livelihoods of 100,000 were lost.

Some suffering is part of existence. Some suffering goes to creatures who have earned it by slacking off and having misplaced values. Some suffering goes to creatures because of what they are, perhaps because they were born without a leg, or they were born with a lower than average IQ. And some suffering goes to creatures who have not earned it at all, like that salmon or that chicken that either one of us might have had today on our plates.

You are a person who has been cursed with an intolerance for other people's suffering. You think this is a good thing, but it's not. Some suffering in nature cannot be helped; we cannot hope to disentangle knots that evolution has created, when the lion's well-being depends on the occasional killing of a completely innocent individual from a herd. We cannot eliminate the suffering of the lion's victim without eliminating lions.

Even if we restrict ourselves to human suffering, then some suffering could be helped now, but the fixes for most suffering are much further away. But what is happening with people like you - people with huge hearts that feel the aches of many others - is that your perception of what can and cannot be done is directed away from rationality by the sheer strength of compassion you feel for some. Because of the acuteness of this feeling, you wish something to be done - even at the cost of retarding growth; even at the cost of other suffering being prolonged in the long run.

If only the Rich White Male was responsible for the deficiencies of sub-Saharan Africans; or if the Rich White Male could at least help them. But he can't. It's not the Rich White Male who made them what they are. It is not Him who gave them curly hair, smooth ebony skin, saggy breasts and long, strong muscles. He tries and He tries, and yet he cannot raise their academic performance. Desegregation, affirmative action, forced busing, nothing helps. It is as though the disadvantage wasn't conveyed on blacks by the Rich Whate Male - it is so intrinsic, it's as though it comes from evolution!

But you'll never give up, will you. Because the Rich White Male is the closest you have to a deity, and as long as you can believe that somehow he can fix things, there is someone to pray to.

Don Geddis said...

First of all, the article you link to doesn't support your summary. This is probably the relevant sentence: The direct effect of genes on IQ accounts for only 36 percent of IQ variance, Flynn tells us, with 64 percent resulting from the indirect effect of genes plus environmental differences uncorrelated with genes.

36% is already a lot, but more important is that the remaining 64% also includes "the indirect effect of genes". It is not the case that Flynn is claiming that genes only contribute 36% to expressed intelligence.

Secondly, the real concern for social policy is whether there are reasonable conscious choices you can make to do anything about the difference. When you talk about low average IQ in Africa (or US blacks), proposed solutions are naturally things like "better schools", "better nutrition", "fewer single-parent households", "a culture of valuing education", etc.

Perhaps it's the case the IQ is strongly environmental, but due to some as yet undiscovered chemical soup in utero. Say, something like the Romans using lead pipes for municipal water, and slowly getting stupid.

Until someone discovers such a link, we can ignore this possibility. Because the main -- surprising! -- lesson from intelligence studies is that all this typical "training" stuff has remarkably little influence on final expressed IQ.

I think the average IQ variation is about 50% accounted for by genetic influences (which is consistent with your Flynn paper). But even more important: it's easy for a bad environment to suppress IQ, but it's very hard to enhance IQ by going from an adequate to a superior environment.

Once you get to average, US, major metropolitan levels of education, nutrition, etc., then the IQ variation due to genetics approaches 100%. It is not the case that the smarter kids were read to more, or went to the museum more often, or watched TV less. It is the case that the smarter kids typically had smarter parents.

An inadequate environment can cause you to fall short of your potential. An adequate environment can allow you to achieve your potential. A superior environment will be of almost no help in exceeding your potential.

And your potential is determined by genetics.

Don Geddis said...

Here's another Flynn example that is worth pondering: If on the basis of their genetic inheritance, separated-twin pairs are tall, quick, and athletically inclined, both members are likely to be interested in basketball, practice assiduously, play better, and eventually attract the attention of basketball coaches capable of transforming them into world-class competitors. Other twin pairs, in contrast, endowed with shared genes that predispose them to be shorter and stodgier than average will display little aptitude or enthusiasm for playing basketball and will end up as spectators rather than as players.

“Genetic advantages that may have been quite modest at birth have a huge effect on eventual basketball skills by getting matched with better environments,” Flynn writes. He suggests a similar environmental influence on genetic inheritance in regard to IQ: Twins with even a slight genetic IQ advantage are more likely to be drawn toward learning, perform better during their primary and secondary education, and thereby gain acceptance into top-tier universities. In the process, their IQ levels are likely to increase even further.


So let's agree with this hypothetical example. What is society to do about it? You've got one kid, with a 140 IQ at age 6. They spend an hour reading, and finish a great book, and love it, and then read for 100 hours in the next month because it is so much fun, and of course a month later are reading a few grades above their typical level.

You've got another kid with 90 IQ, and they spend an hour, and struggle to read a few pages, slowly sounding out every word. And it's no fun, so they quit. And a month later, are way behind the first kid.

Yes, it's certainly the case that if you somehow forced or paid or cajoled the second kid into spending 100 hours reading also, then they wouldn't be so far behind the first one as they now are. Practice helps too.

But the second kid will never get as far in an hour as the first kid does in an hour. And the second kid will never get as far in 100 hours as the first kid does in 100 hours.

What do you propose that society do about this?

You don't have to go so far as to say "the difference in reading ability is primarily genetic", which seems to be the strawman you keep fighting. Of course practice and training matter a lot, in terms of expressed ability.

But is seems as though you desire that, if only we could make environments "the same", then the outcomes would also be the same. (I.e., genetic differences in intelligence aren't important.) That's just never going to happen. All the evidence is overwhelmingly against you that "same environment" can produce same IQ/intelligence.

Even worse, any time you see a difference in expressed outcome, you jump immediately to an accusation of necessarily an environmental lack, because you refuse to credit genetic differences for any significant influence.

denis bider said...

Here are some quotations from a chapter I recently read in Thomas E. Woods's excellent 33 Questions About American History You're Not Supposed To Ask.

From Chapter 9 - "Did desegregation of schools significantly narrow the black-white educational gap?":

Since well before the Brown v. Board of Education school desegregation decision (1954), some social scientists had been arguing that school segregation instilled a sense of inferiority in blacks, thereby harming their academic performance.

[...]

... a study released the previous year by the Department of Health, Education, and Welfare. That study's major conclusions were radically at odds with the typical argument put forward about desegregation and the disparities between black and white schools. Popularly known as the Coleman Report, the study found that black and white schools were in fact roughly similar in expenditures, physical plant, and other resources. Any differences between them were as likely to favor black schools as white.

[...]

By the 1990s billions of dollars had been spent on integration programs by all levels of government. The results? Recent data from the National Assessment of Educational Progress (NAEP) show that the average black student about to complete his senior year of high school performs at a slightly lower level than the average white eighth-grader in reading and American history, and far below the average white eighth-grader in mathematics and geography. Only 3 percent of black students could demonstrate more than a "partial mastery" of the fundamental skills necessary for "proficient work" in twelfth-grade mathematics; for whites the figure was seven to ten times higher.

[...]

The numbers in science show blacks averaging in the eighth percentile in 1977 and in the tenth in 1999. On the math SAT only seven hundred black students in America scored above 700 in the year 2001, while more than sixteen thousand Asian American students did so, in spite of being substantially outnumbered by blacks.

[...]

Behavioral differences are also evident that early, and they persist into the future. On average, black students are much less likely than whites to be described by kindergarten teachers as attentive, eager to learn, and persistent in carrying out assigned tasks, and they are more likely to be described as argumentative, quick-tempered, and violent. These discipline disparities persist over time. Later in life blacks are two and a half times as likely to be suspended or expelled from school as whites. Faced with statistics like these, "civil rights" groups typically accuse white teachers of arbitrarily singling out blacks for punishment. To the contrary, black teachers have been found to be even more critical of black students than white teachers are. Moreover, Asian students are less than half as likely as whites to be suspended or expelled; are we to believe that an antiwhite, pro-Asian bias permeates the American educational system?

[...]

Educational disparities between the races persist even when social class is taken into account. To be sure, students from higher socioeconomic backgrounds do better than students from lower ones, but this phenomenon is true for blacks and whites alike. The racial gap becomes only marginally smaller as we compare blacks and whites from similar backgrounds. A good example is Shaker Heights, Ohio, an affluent Cleveland suburb whose high school spends 50 percent more per pupil than the national average. The town's black residents are only slightly below their white counterparts in education and income levels, but the racial gap in achievement persists there.

[...]

Education scholar David Armor reports that during [1975-1988] "age-nine blacks in segregated schools gained 12 points in reading and 17 points in math, compared with 11 points and 16 points, respectively, for blacks in desegregated schools. For age-seventeen blacks, those in segregated schools gained 34 points in reading and 22 points in math compared to 21 and 17 points, respectively, for those in desegregated schools." Overall, by 1990 there was a difference of only a few points in the reading and math scores of age-nine blacks in (de facto) segregated schools versus those in desegregated schools, and hardly any measurable difference at all in the scores of black seventeen-year-olds.


Ron: so much for environment.