Information Processing

> Doesn't this just mean that IQ Scores don't measure what they're supposed to?

The most cautious defensible position, in my opinion, is that "we can crudely measure a quantity that is related to the folk notion of intelligence"[1]. IQ tests are good, not great, at measuring something which 1) correlates to performance on just about any task that we regard as "mental", and 2) which we are thus far unable to divide any further – it appears to be impossible to split this "something" into a bundle of uncorrelated disparate abilities[2]. This "something" is called general intelligence, or g. However, all IQ tests are trainable and have different emphases; there is no bulletproof g test.

> My understanding is that IQ scores measure how smart you COULD be, all things considered.

The g factor is not a potential. It is defined by statistically extracting a factor common to all (or all minus epsilon) measures of intelligence, which factor is then found – empirically – to predict future performance. It does appear to measure a kind of intellectual potential[3], which is one reason psychologists are interested in it.

So, does this notion of general intelligence contradict the findings linked in this post? Logically, not at all; there is no reason a priori why the general factor should not be malleable. The question is if the general factor is in fact altered. Not an easy question to answer, due to the fact that g, being a statistical construct, cannot directly be measured, but must…

With respect, you sound like you're under the very common misconception that top universities are interested in educating the most academically impressive undergrads, and that it's a fight between parents to see who can trick the school into thinking their child is among the best students. In fact, universities are driven primarily to increase their influence on the world at large.

When hiring professors, this can indeed mean academic acumen is valued, since impressive scholarship shapes the world and brings the university prestige. At the same time, grant-getting abilities are very important, since you can use money to buy influence in lots of ways.

When selecting undergrads, academic ability has some instrumental value but very little intrinsic value to the university. This is because academic-superstar undergrads will leave the university before they exert influence with their scholarship. The universities does wants to mold the minds of future powerful people, and that usually means looking for students who are fairly (though not necessarily outrageously) smart.

But to first order, you can think of the undergraduate program at top universities as a pure money-making venture. The first strategy used is near-perfect price discrimination to maximize immediate returns, i.e. "send us your parent's W2s and we'll tell you how much you'll pay". (Tuition is extremely high but most students get substantial financial aid.) The second strategy is to groom an ideal donor pool…

But does it really matter that the students are not "American-born"?

If you're trying to talk about the impact of American universities on America's innovative capacity and America's economy, then yes, it matters how many students and graduates are American-born -- because only an extreme few of those immigrant students are getting Green Cards. It also matters to consider American-born students rather than all citizens and prospective citizens because we're trying to get an indication of what people think about the American labor market. The best way to measure that is to look at people who are confined to the American labor market.

If we had a "points-based" immigration system like Canada, say, I would be asking how many graduates are American citizens. But we don't. Most international students I met were planning on either going "back home" or rising through further academic degrees (ie: grad-school) in order to continue their visas long enough to at least try for a Green Card and/or American citizenship. The economic impact of the latter is limited to academia.... which gets us back to the very problem I've been trying to articulate: that academia (in the sense of teaching and research, not just university incomes or spending) has been killed off as a major economic engine in America.

http://infoproc.blogspot.co.il/2008/05/dont-become-scientist-philip-greenspun.html -- here is our problem, described twice. American STEM innovation/research is a bad career path. …

In the blogpost

"Roe devised her own high-end intelligence tests as follows: she obtained difficult problems in verbal, spatial and mathematical reasoning from the Educational Testing Service, which administers the SAT, but also performs bespoke testing research for, e.g., the US military. Using these problems, she created three tests (V, S and M), which were administered to the 64 scientists, and also to a cohort of PhD students at Columbia Teacher's College. The PhD students also took standard IQ tests and the results were used to norm the high-end VSM tests using an SD = 15. Most IQ tests are not good indicators of true high level ability (e.g., beyond +3 SD or so)."

Seems a decent try at it to me. But a better indicator that IQ is predictive of success is

http://infoproc.blogspot.com/2009/01/horsepower-matters-psychometrics-works.html

Can psychometrics separate the top .1 percent from the top 1 percent in ability? Yes: SAT-M quartile within top 1 percent predicts future scientific success, even when the testing is done at age 13. The top quartile clearly outperforms the lower quartiles. These results strongly refute the "IQ above 120 doesn't matter" claim, at least in fields like science and engineering; everyone in this sample is above 120 and the top quartile are at the 1 in 10,000 level. The data comes from the Study of Mathematically Precocious Youth (SMPY), a planned 50-year longitudinal study of intellectual talent.

Ability Differences Among People Who Have…

It's only bold because there is a large number of people (often state founded, often controlling at least the lower levels of education, often with major influence on media) who strongly feel otherwise -- with no numbers to back them up, of course.

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If you actually do want to get to the bottom of it, I can heartily recommend Ian Deary's "Intelligence: A Short Introduction" as a place to start.

http://www.amazon.com/Intelligence-A-Very-Short-Introduction/dp/0192893211

(Who knows, if you dig around a bit you might even be able to find a PDF, perhaps at Emil Kirkegaard's website.)

You can also choose to spend an hour on this talk by Stephen Hsu who does research on IQ and genetics:

https://www.youtube.com/watch?v=62jZENi1ed8

You can read some of Plomin's stuff -- he is very much into genetics:

http://www.nature.com/mp/journal/v20/n1/full/mp2014105a.html

There's a paper I can't find at the moment that looks at almost 4000 non-related people, give them an IQ test each + scan their DNA for typical SNPs with a DNA chip. That gives us almost 8,000,000 pairs where we know how similar their IQ score and DNA was. That gives us almost 8,000,000 points we can plot into a 2D coordinate system (and we can of course also throw statistics at them). It turns out that there is a clear correlation between measured IQ and measured SNPs (i.e., the point cloud is denser along a line). In other words, there is a statistical relation between DNA and IQ. This is a result that is…

The paper says:

> The question is whether the bimodality is symptomatic of a poverty trap, namely whether poor people do casual jobs and hold nearly no productive assets because they do not have the talent to do anything else or whether the fact that they are poor prevents them from acquiring the assets needed to climb the occupational ladder.

The cause/effect inversion, of talent/ability => asset acquisition, is always worrying. We might benefit, as a society, if we confront the IQ problem honestly and head-on, in order to have a more complete/accurate policy picture especially because it seems reasonable that wealth transfers should be optimised to enable higher productivity.

Consider: "The Bell Curve Review:IQ Best Indicates Poverty"(Benjamin, 2018), in which:

> I find that IQ is more correlated with poverty than socio-economic-status in every regression, regardless of what is included in the regression, by a factor of 3.

Also: Hsu(2015) https://infoproc.blogspot.com/2015/04/income-weath-and-iq.html

> Income mobility is strongly affected by IQ. In fact, IQ is a much stronger predictor variable than race for escaping the bottom quintile of income.