> Have you not had life experiences where the person with the highest test scores, most amount of praise, recognition, money, earning power, etc., is actually a comparatively ill-equipped human for some task? This intuition should make us skeptical of drawing too many conclusions from such metrics.
1. I'm not saying that people should trust IQ. I'm saying that, to the extent that people trust social science, they should trust IQ more than anything else from the field.
2. There is actually research about what you are talking about[0]:
"The upshot of this research is that work sample tests (e.g., seeing if people can actually do key elements of a job -- if a secretary can type or a programmer can write code ), general mental ability (IQ and related tests), and structured interviews had the highest validity of all methods examined (Arun, thanks for the corrections). As Arun also suggests, Schmidt and Hunter point out that three combinations of methods that were the most powerful predictors of job performance were GMA plus a work sample test (in other words, hiring someone smart and seeing if they could do the work), GMA plus an integrity test, and GMA plus a structured interview (but note that unstructured interviews, the way they are usually done, are weaker)."
This is not to say that IQ is some sort of guarantee - the correlation is only about 0.5. That being said, it is one of the strongest factors; at a population level, it should not be particularly surprising that IQ would have a strong impact on economic success.
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0. https://bobsutton.typepad.com/my_weblog/2009/10/selecting-ta...