Are the SAT and ACT still good IQ tests? We did a survey of high-ability people who were administered an IQ test (CORE) and asked for their modern SAT/ACT scores and found the following: 1. It is much easier to hit the 1600 ceiling on the modern SAT compared to the pre-1994 version. - After fitting a second-degree polynomial regression, we found that scores begin to plateau at approximately 130 FSIQ. Quantile regression estimates the ceiling at around 138 IQ. Visual inspection of the scatter plot also suggests that 1600 scorers begin appearing around the 120-125 FSIQ range and above. - Contrast this with older SAT forms, whose ceilings were far higher, roughly 166 FSIQ. For example, College Board data from the 1984 National College-Bound Seniors cohort showed that only 5 out of 964,739 students earned a perfect 1600. 2. The modern SAT seems to be a slightly worse measure of general intelligence. - The modern SAT was slightly less correlated with IQ compared to older forms, but still a strong proxy (r = ~0.70 with FSIQ after correction for range restriction). Older forms correlated with FSIQ a bit higher, with Frey and Detterman (2004) finding a 0.82 correlation with the ASVAB g-score. - Take this with a bit more caution, considering the sample size is smaller and range restricted. Some caveats though: - The SAT scores are voluntarily self-reported (although the FSIQ scores are not) - The sample size is lower than we'd like and we are still collecting people.

The faculty review at the University of California found that the SAT and ACT were useful predictors of academic success and were not biased against any social group: “Test scores are predictive for all demographic groups and disciplines, even after controlling for HSGPA. In fact, test scores are better predictors of success for students who are Underrepresented Minority students (URMs), who are first-generation, or whose families are low-income: that is, test scores explain more of the variance in UGPA and completion rates for students in these groups.” Ultimately, the faculty committee recommended against going test-optional.

The leading cause of preventable mental impairment in the world is iodine deficiency. The World Health Organization estimates that nearly 50 million people suffer some degree of mental impairment due to iodine deficiency. The good news is that iodine deficiency is inexpensive to cure, costing about 2 to 5 cents per person per year. Eliminating iodine deficiency worldwide is an ongoing project, largely through the introduction of iodized salt (see Iodine Global Network). Iodine supplementation during pregnancy or infancy can raise average IQ by 12 points in severely deficient populations. Ultimately, treating iodine deficiency is one of the most cost-effective ways to raise intelligence and contribute to economic and social development (Zimmermann et al., 2008).

Little-known fact: Some IQ tests include questions about real-life common sense. One Wechsler subtest, Comprehension (CO), presents questions that assess practical judgement, understanding of social norms and proverbs, and the reasoning behind everyday rules. For our Full-scale IQ test (the CORE), we created our own Comprehension subtest. Rather than being read aloud by a proctor, examinees read the questions on screen and type their responses freely. The 0-, 1-, or 2-point partial scoring has been retained; however, for efficiency, an AI scorer has been implemented that compares user responses against a comprehensive rubric defining an acceptable answer and multiple common example responses for each point threshold. Rigorous manual testing and the high internal reliability of this subtest (0.8975) indicate that the AI scoring system is functioning effectively. Moreover, we have found CORE CO's g-loading to be 0.656 (corrected for SLODR), while CO's g-loading on the WAIS-V is 0.66.

"Q: How can we know if our child is intellectually gifted? A: So-called gifted children are not a distinct category of children, set apart from all the rest. Giftedness is part of the total continuum of mental abilities, including both general intelligence and special abilities or talents. Where one draws the line on this continuum to distinguish those one would characterize as “gifted” is fairly arbitrary. In identifying the intellectually gifted, most school systems use the criterion of obtaining an IQ of between 130 to 140 [recte: 120-140 IQ], or higher, on an individual IQ test. ... Aside from the use of psychological tests for identifying the gifted, parents and teachers may notice a number of behavioral characteristics that often distinguish gifted children from their age-mates." Arthur Jensen then quotes directly from an article, describing it as a "highly informative article on recognizing the gifted child".

Common misconception: “IQ doesn't measure anything meaningful beyond 120 IQ and is only good for telling apart intellectual disability." To the contrary: The Study of Mathematically Precocious Youth (SMPY) has tracked thousands of adolescents who scored in the top 1% (135 IQ; 390 or higher SAT-M at age 13) since the early 1970s. The top quartile of this already-elite group went on, by their early 30s, to earn patents at roughly six times the rate of their peers in the bottom quartile, secure tenure-track jobs at top 50 research universities eight times as often, and have incomes in the top 5% of incomes nationwide three times as often (and more, as the attached graph shows). These widening gaps, captured 20 years after the initial testing, show there is no loss in predictive power beyond some threshold of IQ, and that IQ can predict rarer and more prestigious accomplishments later on (Lubinski, 2009).

Higher intelligence predicts lower mortality from all major causes of death. In a study that followed thousands of people for 68 years, higher scores on an intelligence test at age 11 were associated with lower risk of mortality ascribed to coronary heart disease and stroke, cancers related to smoking (particularly lung and stomach), respiratory diseases, digestive diseases, injury, and dementia. There was a ~20% lower risk of all-cause mortality per 1 SD (15-point) increase in IQ. The first figure below shows that the association is generally incremental across the full range of IQ scores. Controlling for confounders such as childhood socioeconomic status only slightly decreases the relationship. The causes of the relationship are not yet fully understood.

The evidence that brain-training games produce real-world benefits is so weak that one company (Lumosity) was fined $2 million for false advertising by the FTC. Over 13,000 customers were given refunds. Lumosity claimed their games could improve school or work performance, ADHD symptoms, and protect against cognitive decline by mitigating dementia. The Federal Trade Commission’s (FTC) evaluation (2016) sums the lesson up well: “Playing Lumosity's games might make you better at those games, the FTC says, but that doesn't necessarily mean it will sharpen your memory or brain power in the real-world. ... If you remember nothing else, remember this: You can be skeptical of any app, product, or service that says it can improve your memory or brain power quickly and easily.”