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Mean IQ of College Grads is Dropping

inductivist.blogspot.com

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Re: Mean IQ of College Grads is Dropping

#11

Post by byrneseyeview »

a-priori wrote: post #8

I have a few issues with this post. First, it's a mistake to assume IQ is a perfect measure of intelligence, especially over long time scales. I'm highly suspicious of psychometrics. Second, I don't understand US race dynamics, but would anyone care to explain why this guy split the data by race, then disregarded all Black data points? Furthermore, it's well-documented that IQ scores are culture-specific. If you're f…

Some countries establish preferential admissions policies to give certain groups benefits and to harm other groups. For example, the US in the early 20th century, and the USSR in the later 20th century, aggressively discriminated against Jews. A group that has different admissions standards will skew your data, so if black candidates can get to the same school with SATs hundreds of points lower, the rise of this bizarre phenomenon will distort the data.

Re: Mean IQ of College Grads is Dropping

#12

Post by dangoldin »

jpeterson wrote: post #2

"Mean IQ of College Grads is Dropping" is basically the same statement as "more people are graduating from college."

Not neccessarily true.

You are assuming that these additional people have an IQ lower than what the average used to be. More people can be graduating from college who have a higher IQ.

An example may be Harvard. Harvard just lowered the tuition for certain incomes, thus more kids can now go to Harvard that were not able to be before due to finances. These kids may have an IQ higher than the average Harvard graduate and they would have increased.

Re: Mean IQ of College Grads is Dropping

#13

Post by lolb »

kingkongrevenge wrote: post #10
a-priori wrote: post #8

I have a few issues with this post. First, it's a mistake to assume IQ is a perfect measure of intelligence, especially over long time scales. I'm highly suspicious of psychometrics. Second, I don't understand US race dynamics, but would anyone care to explain why this guy split the data by race, then disregarded all Black data points? Furthermore, it's well-documented that IQ scores are culture-specific. If you're f…

> I'm highly suspicious of psychometrics. > it's well-documented that IQ scores are culture-specific. Psychometrics is not BS. There's a mountain of data showing properties like IQ (i.e. g) are real, useful measures, not culture specific, and are highly heritable. These are inconvenient truths to a lot of people with egalitarian ideals so there's mountains of FUD clouding the cold hard facts about IQ.

I didn't know Linda Gottfredson posted here.

IQ is a useful (if not especially real) measure, but less so than other measures, it is culture-specific, and it is hardly "highly heritable"; Devlin et al. showed a while back that its narrow-sense heritability is about 35% at best, and most studies of IQ's heritability grossly overestimate it by failing to control for a multitude of environmental effects. And psychometricians don't seem to get how factor analysis renders their beloved general intelligence measure a tautology, so it's understandable why someone would regard their work as BS.

[Edit to add some of the "cold hard facts about IQ" that IQ pushers like the parent comment don't tell you: IQ's heritability varies with socioeconomic status from about 80% to virtually zero, and also increases with age, which makes any claim about IQ having a high heritability across the board extremely suspect.

Note also that despite the name, heritability isn't a measure of 'how genetic' a trait like IQ is; IQ pushers often take advantage of that misunderstanding. Heritability is merely a rough estimate of the ratio of a trait's variance explainable by genetics to the trait's total variance in a population; as such heritability varies between groups, between environments, and between times. It is neither necessary nor sufficient to demonstrate that a trait is 'genetic'.]

Re: Mean IQ of College Grads is Dropping

#15

Post by a-priori »

kingkongrevenge wrote: post #10
a-priori wrote: post #8

I have a few issues with this post. First, it's a mistake to assume IQ is a perfect measure of intelligence, especially over long time scales. I'm highly suspicious of psychometrics. Second, I don't understand US race dynamics, but would anyone care to explain why this guy split the data by race, then disregarded all Black data points? Furthermore, it's well-documented that IQ scores are culture-specific. If you're f…

> I'm highly suspicious of psychometrics. > it's well-documented that IQ scores are culture-specific. Psychometrics is not BS. There's a mountain of data showing properties like IQ (i.e. g) are real, useful measures, not culture specific, and are highly heritable. These are inconvenient truths to a lot of people with egalitarian ideals so there's mountains of FUD clouding the cold hard facts about IQ.

Let me clarify. I don't think psychometrics are BS; I think they are real measures of certain skills. However, the results of IQ tests have certain, significant limitations that people often don't appreciate. In practice, the tests are overused and the results are over-generalized. This article is a prime example of my criticisms.

Re: Mean IQ of College Grads is Dropping

#16

Post by etal »

kingkongrevenge wrote: post #10
a-priori wrote: post #8

I have a few issues with this post. First, it's a mistake to assume IQ is a perfect measure of intelligence, especially over long time scales. I'm highly suspicious of psychometrics. Second, I don't understand US race dynamics, but would anyone care to explain why this guy split the data by race, then disregarded all Black data points? Furthermore, it's well-documented that IQ scores are culture-specific. If you're f…

> I'm highly suspicious of psychometrics. > it's well-documented that IQ scores are culture-specific. Psychometrics is not BS. There's a mountain of data showing properties like IQ (i.e. g) are real, useful measures, not culture specific, and are highly heritable. These are inconvenient truths to a lot of people with egalitarian ideals so there's mountains of FUD clouding the cold hard facts about IQ.

Let's raise the bar a little:

http://cscs.umich.edu/~crshalizi/weblog/523.html

The g that shows up when doing factor analysis on intelligence test results is not necessarily the same concept we all have of innate, immutable intelligence. There are good reasons to believe it's not the same thing at all -- g is mutable, somewhat heritable, and quite variable between different cultures and countries. It's a broad correlation; it doesn't correspond to any particular fundamental brain mechanism that would tell us useful things about biology.

Re: Mean IQ of College Grads is Dropping

#17

Post by etal »

comatose_kid wrote: post #3

The author's conclusion that lowered admission standards are why IQ has dropped is suspect. Any number of factors could be causes for this (ex: the average amount of TV watched by a student may have increased over the last 40 years).

Given his conclusion and brief rant, you'd think it would occur to him to grab data about the percentage of the population with a bachelor's degree for each decade, and plot that versus the IQ data.

(No, I wasn't going to, it's not my rant.)

Also, there's zero discussion of the scores ticking back up from the 1990s to the 2000s. Stricter admissions standards? Somehow that doesn't seem likely. Teaching against standardized tests in high school helping students to score better on the standardized IQ test? Better than nothing.

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