Comment by chrisco255 | Hacker News Reader

Comment by chrisco255 | Hacker News Reader

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It's not just me. It's 100+ years of psychological evidence. It is the strongest psychological test we have. The military uses similar concepts in the AFQT to determine suitability for recruitment and advancement for certain positions. The military has been using concepts like this since World War I, where it was important to scale up a military quickly. Our survival depended on having smart people with disparate educational backgrounds (remember the U.S. was much more rural and less educated than today) in the right places, rapidly. How do you do this without IQ tests?

'One study on nine groups of soldiers differing in job and reading ability found a correlation of .96 between the AFQT and reading achievement (Sticht, Caylor, Kern, & Fox, 1972)... Another study obtained reading scores for 17-year olds for those same ethnic groups and dates (Campbell et al., 2000) and found a correlation of .997 between reading scores and AFQT scores.' [1]

'Cognitive ability tests taken at age 11 correlate 0.81 with national school examinations taken at age 16.' [2]

Note that .96 and .81 are huge correlations. These results have been replicated across 100+ years of psychological research across cultural boundaries and across multiple disciplines.

Can you make up for lower IQ with higher work ethic? Yes, but like a shorter than average NBA player, you're going to be at a disadvantage. By no means does the existence of shorter than average NBA players suggest that you should expect shorter than average men to be just as likely to succeed as taller than average men.

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[1] https://files.eric.ed.gov/fulltext/ED101297.pdf [2] https://emilkirkegaard.dk/en/wp-content/uploads/Intelligence...

> It is the strongest psychological test we have. [...] The military has been using concepts like this since World War I, where it was important to scale up a military quickly.

While I don't dispute that IQ tests correlate with smarts, the argument that "The WW1 military was very motivated, therefore their decisions must have been rational" isn't a particularly good one IMHO - because there are a great many counter-examples.

Sure, because what did society do before IQ tests? Surely because they've been around for that long, they must be flawless.

https://www.independent.co.uk/news/science/iq-tests-are-fund...

“It has always seemed to be odd that we like to call the human brain the most complex known object in the Universe, yet many of us are still prepared to accept that we can measure brain function by doing a few so-called IQ tests,” Dr Highfield said.

I wonder, what is your opinion on Murray's and Herrnstein's The Bell Curve?

I don't think it's a perfect measure but it's the best we've got. No other psychological measure has the predictive power of IQ tests. The key to a good experiment is it's predictive capacity. IQ tests are very good predictors of reading comprehension, academic outcomes, and economic outcomes. If a weather forecast 5-20 years into the future were to hit the mark 80-90% of the time we would call that a great model.

If said model only predicted whether it will rain or not.

But not really. You pulled those numbers out of the air, and they aren't very descriptive.

Will someone with a 140 IQ fair better academically and economically than someone with 130 90% of the time?

140 vs 100, sure. But as the # of standard deviations converges, it's less meaningful. And there are still other covariant factors you are failing to consider, as mentioned before.

The point is that no matter which way you slice it, IQ stands out.

On average, people raised in poor environments who have higher IQ do better than people raised in poor environments with lower IQ. More likely to be more upwardly mobile, more likely to be more whatever.

And on average, people raised in good environments who have higher IQ do better than people raised in good environments who have lower IQ.

If you're a person of color, on average, you're going to do better if you have a higher IQ than if you have a lower IQ.

Same if you're a woman.

And 140 vs 130 is a bit unfair. You're talking about looking for meaningful differences between less than 2% of the population as compared to less than 0.1% of the population.

And just because there are diminishing returns with something like IQ, doesn't make it useless.

And 140 vs 130 is a bit unfair

That wasn't the point. I would say the same for 100 and 110.

Some MENSA members in this thread seem very attached to their scores.

100 and 110 you might see more differences in the aggregate.

That's the other thing, you do have to look at the whole. Because there is likely overlap. But the trend of note is that IQ tracks through it.

If you sort people by earning potential, you'll find that as average income goes up, so does average IQ.

When you sort by health outcomes. As average healthiness goes up, so does average IQ.

Even the outcomes that are colloquially contrasted with intelligence actually correlate well. In other words, if you sorted people by EQ, you'll find that better average EQ means better average IQ.

IQ is the aspartame of psychology. So maligned that it's been probably studied more than other things. And just like aspartame is perfectly fine, IQ does what it says on the tin.

It is an indicator. Not a rule.

100 vs 140 will be a very strong indicator. 100 vs 110 will not; I would not trust 110 to yield a better outcome 80-90% of the time, as GP claimed.

Which is why the comparison of IQ scores at that coarseness is plain silly.

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