Astral Codex Ten

Mensa

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Mensa

Article

Mensa is a recurring organization in the Astral Codex Ten archive, appearing 3 times across 3 issues between February 18, 2021 and March 20, 2024. The archive places it in contexts such as “Admit to being a member of Mensa”; “the older studies got their very-high-IQ samples from Mensa”; “testing sessions by Mensa (yes, I know you all hate Mensa, but their IQ tests are considered pretty accurate)“. It most often appears alongside Twitter, ACT, Alex.

Metadata

  • Category: Organizations
  • Mention count: 3
  • Issue count: 3
  • First seen: February 18, 2021
  • Last seen: March 20, 2024

Appears In

Source Context

Recovered passages from the original issue text. When the raw archive preserved outbound links inside the source passage, they are listed directly under the quote.

Book Review: The Cult Of Smart
February 18, 2021 · Original source
But the opposite is true of high-IQ. Society obsessively denies that IQ can possibly matter. Admit to being a member of Mensa, and you'll get a fusillade of "IQ is just a number!" and "people who care about their IQ are just overcompensating for never succeeding at anything real!" and "IQ doesn't matter, what about emotional IQ or grit or whatever else, huh? Bet you didn't think of that!" Science writers and Psychology Today columnists vomit out a steady stream of bizarre attempts to deny the statistical validity of IQ.
Links For March 2023
March 10, 2023 · Original source
24: Related: The Mensa Fallacy. Many older studies show that very-high-IQ people are mentally imbalanced, bad at real-world tasks, or unambitious. Newer, more representative studies don’t show this. The most likely explanation: the older studies got their very-high-IQ samples from Mensa, the most convenient place to find lots of very-high-IQ subjects. But within the population of very-high-IQ people, Mensa is adversely selected for non-IQ traits; geniuses who are mentally healthy and ambitious are probably inventing quantum computers at MIT or making bank on Wall Street; it’s the geniuses who can’t make it in regular society who are going to every Mensa to boast about how quickly they can solve Rubik’s Cubes. Any study that uses a Mensa sample to study very-high-IQ people and conclude that they’re defective should be considered suspicious.
Inline links: The Mensa Fallacy
The Mystery Of Internet Survey IQs
March 20, 2024 · Original source
The average ClearerThinking user reported their IQ as 130. These are implausibly high. Only 1/200 people has an IQ of 138 or higher. 1/50 people have IQ 130, but the ClearerThinking survey used crowdworkers (eg Mechanical Turk) who should be totally average. Okay, fine, so people lie about their IQ (or foolishly trust fake Internet IQ tests). Big deal, right? But these don’t look like lies. Both surveys asked for SAT scores, which are known to correspond to IQ. The LessWrong average was 1446, corresponding to IQ 140. The ClearerThinking average was 1350, corresponding to IQ 134. People seem less likely to lie about their SATs, and least likely of all to optimize their lies for getting IQ/SAT correspondences right. And the Less Wrong survey asked people what test they based their estimates off of. Some people said fake Internet IQ tests. But other people named respected tests like the WAIS, WISC, and Stanford-Binet, or testing sessions by Mensa (yes, I know you all hate Mensa, but their IQ tests are considered pretty accurate). The subset of about 150 people who named unimpeachable tests had slightly higher IQ (average 140) than everyone else. Thanks to Spencer Greenberg of ClearerThinking, I think I’m finally starting to make progress in explaining what’s going on. Problem #1: The Biggest SAT → IQ Conversion Site Is Wrong Thanks to Sebastian Jensen for pointing this out! He writes: A search of ‘SAT to IQ’ on google results in being presented with the website ‘iqcomparisonsite.com’. This man has directly converted the SAT percentiles to IQ scores, which is not what should be done. Tests like the ACT and SAT correlate with IQ at about 0.8-0.85 [rca], [my analysis], [emil article], [scholarly article]. The general factor of academic achievement and IQ correlate at about 0.81-0.88 [psychometric test], [GCSE grades]. This discrepancy occurs because they measure different abilities - an IQ test will test many different abilities, while the SAT/ACT only tests verbal/mathematical ability. In addition, these percentiles are very outdated as the average SAT score has changed over time due to changes in the content of the test. Instead, the ideal way to do this is to take the percentiles from the current versions of the SAT and then convert those into z-scores and then regress those z-scores by the mean by the estimated regression coefficient. Using Sebastian’s updated tables, we find that the average Less Wrong IQ as predicted by SATs goes down from 140 → 132, and the ClearerThinking IQ goes down from 134 → 124. So people probably exaggerated their IQs somewhat, and unrelatedly we were using an SAT → IQ conversion that exaggerated IQs, and so the numbers falsely appeared to match. Okay! It’s a start! Interlude: The ClearerThinking IQ Test The ClearerThinking survey included a battery of cognitive tests of exactly the sort that could usually be used to determine IQ. Unfortunately none of them were normed, so we know how all the 3700 subjects did relative to each other, but not where the 100 point is. Spencer was able to norm them to the general population based on education level. That is, he asked his sample about their educational attainment (college degree, PhD, etc) and found they were a little more educated than the US average. Since the US average IQ is 100, his sample should have an average a little higher than this. He was able to calculate how much higher. Then he mapped a bell curve to everyone in his sample’s performance on his tests. Since he had 3700 people, he was able to do this relatively smoothly. He found an average IQ of 110, which originally surprised me, because I thought his sample was supposed to be random crowdworkers, who should be close to the US average of 100. But in fact, his survey was a combination of 1900 crowdworkers and 1800 people who saw it on social media - eg friends and friends-of-friends of Spencer. Separating this out by group, we find that the crowdworkers have an average normed-IQ of 100, and the social media referrals have an average normed-IQ of 120, making the overall average of 110. This seems pretty trustworthy, since it correctly estimates the crowdworkers (completely average) as 100. Spencer studied math at Columbia, his friends and friends-of-friends are pretty smart, and I think the 120 estimate for them is also okay. But there’s still a problem here. Using an accurate SAT score → IQ calculator, we determined that the ClearerThinking average should be 124. But using real cognitive tests, it looks like it’s 110. What went wrong? Problem #2: Only The Smartest People Report Their SATs Using Spencer’s cognitive test results, we can compare people who did vs. didn’t take the SAT. We find: People who didn’t take the SAT (remember, this includes current high schoolers) have tested-IQ 110.
Inline links: corresponding to, for pointing this out!, [rca], [my analysis], [emil article], [scholarly article], [psychometric test], [GCSE grades], changed
It looks like up to about 140, self-reported IQ and normed IQ rise together, and then the relationship breaks down. Sure enough, looking at the subset of self-reported IQ scores below 140, the correlation with tested IQ rises to .6, and looking at the subset above 140, the correlation is nonsignificant at -0.02. I don’t want to assert that the breakpoint is exactly 140, but I do think the test stops working somewhere in the 130 - 140 range. But this can’t be the whole problem. Notice that people who reported getting scores around 100 on previous IQ tests overwhelmingly got scores less than 100 on this one. So are people just taking terrible Internet IQ tests that inflate their score about 20 points? The ClearerThinking sample didn’t ask people what IQ test they took, but the LessWrong sample did. It found approximately the same score from WAIS, WISC, Stanford-Binet, and Mensa - all of which were about 10 points above what you would predict from SAT scores. So I think there are two things going on: The main problem in the LessWrong sample, and the far right end of the ClearerThinking sample, is that even official IQ tests are gobbledygook over 135. Any numbers above this should be rounded down to 135, no matter how venerable the test involved.