“Low Base Rates Prevented Terman from Identifying Future Nobelists”, 2019-08-28 (; backlinks; similar):
Although the accomplishments of the 1,528 subjects of the Genetic Studies of Genius are impressive, they do not represent the pinnacle of human achievement. Since the early 1990s, commentators (eg. Bond, 2014; Gladwell, 2006; Heilman, 2016; 1992) have drawn attention to the fact that two future Nobelists—William Shockley and Luis Alvarez—were among the 168,000 candidates screened for the study; but they were rejected because their IQ scores were too low. Critics see this as a flaw of Terman’s methodology and/or intelligence testing. However, events with a low base rate (such as winning a Nobel prize) are difficult to predict (1939).
This study simulates the Terman’s sampling procedure to estimate the probability that Terman’s sampling procedure would have selected one or both future Nobelists from a population of 168,000 candidates. Using data simulations, we created a model that realistically reflected the test-retest and split-half reliability of the IQ scores used to select individuals for the Genetic Studies of Genius and the relationship between IQ and Nobelist status.
Results showed that it was unlikely for Terman to identify children who would later earn Nobel prizes, mostly due to the low base rates of such high future achievement and the high minimum IQ needed to be selected for Terman’s study.
Changes to the methodology that would have been required to select one or both Nobelists for the longitudinal study were not practical. Therefore, Alvarez’s and Shockley’s absence from the Genetic Studies of Genius sample does not invalidate intelligence testing or Terman’s landmark study.