> Don't legitimate IQ tests top out at 160 for adults?

“Top out” can be interpreted many ways. It depends on how they are used.

Modern tests are fairly accurate up to 2sd (70-130). The tests start wavering in accuracy between 2sd and 3sd (55-70 and 130-145).

Over 3sd, and the only thing one can confidently say is that the examinee is most likely lower or higher than 3sd (55 and 145). The tests just don’t have enough data points to discriminate finely beyond those thresholds.

Let me further say that, on the high end, there are very few jobs for which I would make any selection decision based on how high an IQ score (or proxy thereof) is over 130. There are other variables, many of which are easier to measure, that are better predictors of success.

All of this doesn’t even take into consideration that there is relatively more type II error/bias in IQ results — that is, there are plenty of people who score less than their theoretical maximum (e.g., due to poor sleep the previous night), while there are relatively fewer people who score much higher than their theoretical maximum.

Yes they do. Not that it ever stopped people from making claims about having higher IQ.

IQ 160 means that you are 1 in 30,000 of your age group. That means that to calibrate a test that can measure that high, the authors had to test more than 30,000 people in each age group (depending on what statistical certainty you need, but it could be 10x the number for reasonable values). Not sure how large the age groups typically are, but the total number of people necessary for calibration is counted in millions. You have to pay them all for participating in the calibration, and that's not going to be cheap.

And with values greater than IQ 160, the numbers grow exponentially. So I am rolling to disbelieve than anyone actually calibrated tests for such large numbers. (Especially once the numbers start to exceed the total population of Earth, which is around IQ 190.)

There are separate tests for the extremes, but obviously less researched because the further out you go the less they have to work on.

Many years ago, while unemployed, I was sent for a intelligence and dyslexia test (because of the very same perceived waste of potential that the article talks about). I was not dyslexic but scored above the range that the intelligence test could measure. The professor(I believe he was moonlighting for research funding) performing the test talked about the upper range tests, but said they were very long, required specialists to conduct and there's seldom any reason to investigate where you are in the upper range.

Then we went on to waste a huge amount of time talking about human perception and I remember describing an idea that finally seems to be feasible because the new Steam VR headset does it and calls it Foveated rendering.

I can't specifically recall the date of this but the tester was recording results on his palm pilot, which was a flash new thing at the time.

Usually. There's diminishing returns the higher you go. The difference between 150 and 175 is much smaller than 125 and 150.

When you go from 30 seconds to 15 seconds to solve a problem, that's noticeable. But when you go from half a second to a quarter of a second, the difference doesn't really matter.

So a lot of IQ tests have some sort of ceiling where the only thing they can tell you is "Yeah, it's more than this".