> Why would any rational individual take an IQ test? IQ cannot be changed and whatever outcome doesn't change your course of action

From what I can tell, most professions have a rough IQ floor. If you're above the floor, more IQ can always help, but other traits like conscientiousness and agreeableness tend to matter more. But if you're substantially below the floor, there's almost no chance that hard work will help you bridge the gap.

Have you taken one?

It certainly felt like the kind of test that could be improved with practice. Not as easily as the SAT, sure, but certain patterns seemed to appear, in a way I bet I could prep for.

I haven't tested that hypothesis, but if anyone wants to fund me to take a bunch over the next year... let me know ;)

(Why did I take it in the first place? Curiosity. Maybe also a bit of vanity. "Rationality" seems like a false idol to focus purely on in general, for decisions.)

I've taken at least 5 over the course of my life. Possibly a 6th that I didn't know about (possibly age 5 or 6?), but I know of taking multiple between ages 9 through mid 30s.

Regardless of the test, the percentile numbers didn't change.

I've read people claim on and off for years that you can "study" for them and "improve" your scores, but that's not been my experience. Any variations you get might be slight, but you're extremely unlikely to get any statistical difference... unless....

I had a test at age 9 for a specific 'gifted' program starting in our school district. 2 months later, we moved districts, and I was given the exact same test again. I aced it, because I'd asked my parents some of the questions I didn't understand the first time. I 'confessed'(?) to the test giver in the second district that I'd already had these exact same questions 3 months earlier, which they noted. I'd already 'qualified' after the first test, so again, I don't think there was any significantly different outcome (I 'qualified' after the second test in the new district as well).

IQ scores do change over time, largely as a function of curiosity and conscientiousness. You could be a genius toddler but if you fail to learn, your IQ continually diminish relative to your peers

IQ has a map/territory problem as well. The theory is that you have some underlying IQ, and the test is a tool to determine what your IQ is. It is well established that practice can improve your score on an IQ test. However, that does not imply an improvement in your underlying IQ.

Close. Improving your score on an IQ test does improve your IQ. Your IQ is literally that score. What it does not improve is g, your underlying general intelligence.

You could change your life/career plans based on the results. Whether to go to college or not, whether to pick a job that pays well immediately or one with more potential for long-term advancement, that sounds like the kind of decision where knowing your IQ would help.

No. Whatever your IQ you should aim high and let nature put you in your place.

you cannot pre-emptly put yourself in your place, that’s the best route for depression and depression sucks whether you have a high, normal or low IQ

So much for being rational.