THREAD: 12 Things Everyone Should Know About IQ

1. IQ is one of the most heritable psychological traits – that is, individual differences in IQ are strongly associated with individual differences in genes (at least in fairly typical modern environments). https://t.co/3XxzW9bxLE

2. The heritability of IQ *increases* from childhood to adulthood. Meanwhile, the effect of the shared environment largely fades away. In other words, when it comes to IQ, nature becomes more important as we get older, nurture less. https://t.co/UqtS1lpw3n
3. IQ scores have been increasing for the last century or so, a phenomenon known as the Flynn effect. https://t.co/sCZvCst3hw (N ≈ 4 million)

(Note that the Flynn effect shows that IQ isn't 100% genetic; it doesn't show that it's 100% environmental.)
4. IQ predicts many important real world outcomes.

For example, though far from perfect, IQ is the single-best predictor of job performance we have – much better than Emotional Intelligence, the Big Five, Grit, etc. https://t.co/rKUgKDAAVx https://t.co/DWbVI8QSU3
5. Higher IQ is associated with a lower risk of death from most causes, including cardiovascular disease, respiratory disease, most forms of cancer, homicide, suicide, and accident. https://t.co/PJjGNyeQRA (N = 728,160)
6. Higher IQ is associated with lower rates of most forms of mental illness. https://t.co/0jX1og7xHV (N = 1,049,663)
7. More generally, IQ tests are among the most reliable, predictive measures in psychology – one of the field's crowning achievements. https://t.co/a9z9GPQYuD

If IQ isn't a valid concept, no concept in psychology is valid.
8. Despite this, many people are allergic to the concept of IQ. Ironically, this includes many intellectuals. https://t.co/ThPkVT8apc
9. Perhaps as a result, there's some evidence that researchers are less likely to publish studies showing a link between IQ and grades – the reverse of the usual publication bias for positive findings. https://t.co/gTiKmmarTB; although see https://t.co/sYEgBnaJkO
10. The antipathy to IQ is unfortunate. IQ predicts all things good. Interventions to boost IQ (such as salt iodization) could greatly enhance human well-being. https://t.co/LHVqClN2kE

Conversely, IQ-denial could cause real harm by stalling the development of such interventions.
11. IQ testing has other potential benefits as well. One of my favourite studies of the last few years found that universal IQ screening boosts the number of poor, female, and minority students in gifted education. https://t.co/5at8wNjKe8

Figure: https://t.co/fogF8GyO8Z
12. Last but not least, here's a list of ten common myths about IQ. https://t.co/DOTDWhMoyS HT @StuartJRitchie

More from Life

"I lied about my basic beliefs in order to keep a prestigious job. Now that it will be zero-cost to me, I have a few things to say."


We know that elite institutions like the one Flier was in (partial) charge of rely on irrelevant status markers like private school education, whiteness, legacy, and ability to charm an old white guy at an interview.

Harvard's discriminatory policies are becoming increasingly well known, across the political spectrum (see, e.g., the recent lawsuit on discrimination against East Asian applications.)

It's refreshing to hear a senior administrator admits to personally opposing policies that attempt to remedy these basic flaws. These are flaws that harm his institution's ability to do cutting-edge research and to serve the public.

Harvard is being eclipsed by institutions that have different ideas about how to run a 21st Century institution. Stanford, for one; the UC system; the "public Ivys".

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