Comments on the article Proxying Human Capital:
Tim Lundeen writes: There is an interesting analysis based on the IQ of Nations [here and here]. This analysis shows a 0.9 correlation between the "smart fraction" of a country with verbal IQ over 106 and per capita GDP. This is an astounding number, if it is in fact correct.
Raw data:
The Hypothesis (Smart Fraction Theory II):
where IQ0 is the threshold IQ, Pi(t) is the IQ density function of nation i and zi is a vector with control variables which are allowed to enter in a non-linear fashion (acutally, it should be an "economic system" dummy).
I really enjoyed reading the article (although it is clear that the smart fraction variable is endogenous (Mean IQ is a function of GDP per capita, this holds at least for the poorest and malnourished countries) and then there is always the problem of multicollinearity); see Tyler's post on Education and Economic Development). Maybe of interest: I run the regression ln(gdp per capita) = α + β(mean iq) (semi-log model) and could explain actually the same amount of variation as the La Griffe du Lion model ;-D.
Tim Lundeen writes: There is an interesting analysis based on the IQ of Nations [here and here]. This analysis shows a 0.9 correlation between the "smart fraction" of a country with verbal IQ over 106 and per capita GDP. This is an astounding number, if it is in fact correct.
Raw data:
The Hypothesis (Smart Fraction Theory II):
In market economies, per capita GDP is directly proportional to the population fraction with verbal IQ at or above some determinable threshold.More technically:
where IQ0 is the threshold IQ, Pi(t) is the IQ density function of nation i and zi is a vector with control variables which are allowed to enter in a non-linear fashion (acutally, it should be an "economic system" dummy).
I really enjoyed reading the article (although it is clear that the smart fraction variable is endogenous (Mean IQ is a function of GDP per capita, this holds at least for the poorest and malnourished countries) and then there is always the problem of multicollinearity); see Tyler's post on Education and Economic Development). Maybe of interest: I run the regression ln(gdp per capita) = α + β(mean iq) (semi-log model) and could explain actually the same amount of variation as the La Griffe du Lion model ;-D.
Mahalanobis - am 2004-09-28 04:24 - Rubrik: economics
Ostracised meinte am 28. Sep, 10:13:
Interesting but very touchy stuff. It reminds me of this argument against human cloning that says, ignore all other arguments, just look at the types who are interested in this to understand it should not be allowed. The pages you link to include little-argued statements like "The arrow of cause points mostly from IQ to income, and not the other way round." or this jewel from Steve Sailer, who first writes "it is hard to avoid concluding that intellectual and income differences between nations stem to some extent from genetic differences. The results simply cluster too much by race" and then imparts the following wisdom on us "But it could also be that freedom exercises the brain - West Germans averaged 103 while East Germans scored only 95. My pet theory is that having to make all the choices between products available in a successful capitalist economy stimulates mental development. (I believe this because, as I get older and stupider, I increasingly find shopping to be intellectually exhausting.)" Not convinced here. Yes, I am aware that you personally advocate caution in your post.
Mahalanobis antwortete am 28. Sep, 13:25:
Re:
>>The arrow of cause points mostly from IQ to income,>>and not the other way round.
Although I am convinced that this statement holds at the
microlevel, I would agree with: At the macrolevel, the relation-
ship is bidirectional, but the arrow of cause points mostly
from income to IQ (especially when keeping the LDCs in mind).
Let's run some "causality tests" ;-D.
>>some extent from genetic differences
Oops, I guess I missed that part... I'll remove the link.
Mahalanobis meinte am 28. Sep, 17:42:
Fwd: Re: IQ and the Wealth of Nations
From: Abiola LapiteHello,
I greatly enjoy reading your blog, as most of the time I find myself learning something new and interesting I hadn't seen before. However, I'd be wary if I were you of leaning on "IQ and the Wealth of Nations", the quality of the data of which is (to put it very kindly) *questionable*, and driven as much by Richard Lynn's eugenic and racist fixations as anything else. For more, see here, and I also highly suggest looking at the dataset posted here by Steve Sailer yourself. Note that adjustments for the Flynn effect are ad hoc, applying to some and not to others, that sample sizes are often ridiculously small, and that absolutely no information on the moments of the test scores is disclosed. Does it really pass the smell test with you that an entire third of the population of sub-Saharan Africa is so retarded as to require institutionalization?
The bottom line is that the reason the data in "IQ and the Wealth of Nations" seems to have such predictive power is that it was largely *cooked up* to reflect the economic data. I've been fighting the racist claptrap being pushed by Richard Lynn and his fans for ages now, and it saddens me to see yet another individual whose writing I admire succumb to their junk. Do not be seduced by the fancy integrals being applied to the data: this "research" deserves to be consigned to the same graveyard as the old "Rassenkunde", and for much the same reasons.
My reply:
Thanks for writing!
ad smell test: I obtained the data from the La Griffe du Lion site; they don't provide any information on higher order moments, the sample size, etc. This is one of the reasons why I didn't come up with any estimates. I removed the link to Steve Sailer's site after ostracised pointed out that he refers to genetics in his article. What I do believe: IQ is not only determined by nature but also by nurture and if somebody told me that most inhabitants of sub-Saharan Africa can be regarded as retarded (relative to IQ levels in developed countries), I wouldn't doubt those findings.
