155estimated IQ points
Simonton 2006 Table 1 II-C (2C) estimate
Table 1 column II-C is 155.2 (displayed as 155). II-C is the ages 18–26 estimate corrected for data reliability. Simonton also reports I-U, I-C, and II-U; those other variants are lower or equal. 2C is still a model, not a test.
Simonton 2006 2C estimate: 155. Historiometric model, not a measured IQ score.
Method and limits
Simonton used expectation-maximization with prior biographical ratings of intellectual brilliance, openness, and the limited Cox retrospective estimates. This atlas ranks and displays column II-C.
- No administered IQ test underlies this record.
- The models depend on historical biographical ratings and assumptions about missing values.
- Displaying 2C as one number is a ranking convention, not proof of a test result.
- II-C is the most generous of the four variants; the lower variants would produce a lower or equal estimate.
Uncertainty: 2C is one of four published model variants, not a confidence interval or an administered test score.