The hottest Psychometrics Substack posts right now

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Unlocking a Taxpayer-Funded Dataset

Cremieux Recueil • 465 implied HN points • 19 Mar 26
🔬 Science Psychometrics
  1. The National Collaborative Perinatal Project was fully digitized and modernized into a public, searchable dataset with precomputed variables and kinship links, enabling sibling- and cousin-based analyses; the data and code are openly available for researchers to use.
  2. Analyses support a real general intelligence factor (g) that is strongly linked to genetic influences, with little evidence that aggregate gene–environment interactions matter, though shared environment contributes more to verbal and academic subtests.
  3. Within-family tests show breastfeeding has no clear effect on IQ and socioeconomic effects on IQ are much smaller than cross-sectional estimates; the Black–White IQ gap at age seven is estimated to be largely genetic (~65–69% of the common variance) and brain size correlates with IQ but is largely explained by IQ.

Sex Differences in Intelligence

Cremieux Recueil • 295 implied HN points • 20 Feb 26
🔬 Science Psychometrics
  1. Average general intelligence (g) is essentially the same for men and women. Any mean gap is vanishingly small (on the order of a few tenths of an IQ point) and not practically meaningful.
  2. Men show greater variability in intelligence and test scores, producing more males at both the high and low extremes of the distribution.
  3. Most observed sex differences come from specific skills and test-level abilities (e.g., processing speed, technical knowledge, math/verbal), which appear more malleable and can change with development — for example, early female advantages often fade by adulthood.

The Other Type of Flynn Effect

Cremieux Recueil • 235 implied HN points • 23 Feb 26
🔬 Science Psychometrics
  1. Many reported Flynn and anti-Flynn effects are driven by measurement bias—tests change meaning across cohorts and norms get obsolete—so gains often reflect test-taking sophistication more than real changes in general ability.
  2. Some apparent cohort trends are actually sampling or compositional artifacts, for example later-born children tending to have more advantaged parents, and those apparent gains or losses often disappear in within-family (sibling) comparisons.
  3. Robust conclusions require checking measurement invariance, using within-family designs, and guarding against collinearity and low power; when those methods are applied, large population IQ shifts usually shrink or vanish.

Are Girls Smarter Than Boys?

Cremieux Recueil • 277 implied HN points • 13 Feb 26
🔬 Science Psychometrics
  1. Changing test scoring to reward calibrated confidence and risk behavior instead of just right-or-wrong answers can make women appear smarter even though it measures a different thing.
  2. Including metacognitive calibration, confidence, and risk preference in an intelligence score mixes non-intelligence traits into the measure and can break the usual positive correlations across cognitive tests, producing misleading factor patterns.
  3. The correct way to compare sexes on intelligence is to use a large, diverse test battery, score accuracy normally, and compare the general intelligence factor; redefining intelligence without strong justification is not acceptable.

GDP is Inevitable

Cremieux Recueil • 477 implied HN points • 17 Dec 25
🔬 Science Psychometrics
  1. When you add up many positively correlated variables with positive weights, different composite scores tend to become very similar because shared covariance grows faster than unique variance, so the sums converge toward perfect correlation as components increase.
  2. GDP will naturally correlate highly with lots of other measures since it aggregates overlapping components (and is sometimes included in other indexes), and aggregation reduces within-group noise which mechanically inflates between-group correlations.
  3. Adding items to make a composite more reliable often makes it harder to distinguish from other composites, so improving reliability can reduce discriminant validity (for example, measures like grit can converge with conscientiousness).
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Personality around the world

Vectors of Mind • 216 implied HN points • 16 Mar 23
🔬 Science Psychometrics
  1. Personality models show consistent traits across languages, especially the Big Two: social self-regulation and dynamism.
  2. Understanding personality across languages requires bilingual cohorts or careful translations, as words may not have direct equivalents.
  3. Research suggests that analyzing language models in multiple languages could lead to a universal model of personality, potentially superior to the Big Five.

EQ > IQ

Vectors of Mind • 176 implied HN points • 04 Aug 23
🔬 Science Psychometrics
  1. Emotional Intelligence (EQ) is argued to be more fundamental to human evolution and the 'Good Life' than Intelligence Quotient (IQ), despite being harder to measure.
  2. Traits exist both as idealized forms and measurable approximations through psychological instruments like surveys, but the accuracy of these measurements is limited.
  3. The General Factor of Personality (GFP) is emphasized as a more fundamental concept than the general factor of intelligence (g), with language reflecting its importance and complexity.

How Intelligent is the Average Rationalist?

sebjenseb • 157 implied HN points • 03 Jul 23
🔬 Science Psychometrics
  1. The average IQ of rationalists may not be as high as self-reported values suggest, with estimates pointing to an average IQ between 125-130.
  2. Analysis of SAT and IQ scores of rationalists indicates an estimated average IQ of about 133.6 after accounting for biases.
  3. Educational attainment and plausible assumptions suggest the average IQ of internet rationalists is between 125-130, considering selection for educational attainment.

Nonhuman Intelligence

Cremieux Recueil • 199 implied HN points • 07 Mar 24
🔬 Science Psychometrics
  1. It's challenging to compare intelligence between humans and nonhuman species like apes due to the lack of suitable cognitive tests.
  2. Machine intelligence testing is complex, and comparing it to human intelligence is not straightforward.
  3. Comparing intelligence across different groups may be hindered by factors like age and methodological barriers.

The Stuff of Thought and Feeling

Holodoxa • 59 implied HN points • 26 Feb 23
🔬 Science Psychometrics
  1. Paul Bloom's book 'Psych' offers a comprehensive overview of modern psychology focusing on foundational concepts and influential psychologists.
  2. The book addresses controversial psychological ideas and presents commentaries on existing research, making it accessible yet thoughtful.
  3. Readers may find particular value in the Foundations and Differences sections, and while the book lacks in-depth methodology discussions, it provides a solid introduction to the field.

The State of 'the Gaps' 2022-23

Cremieux Recueil • 96 implied HN points • 31 Dec 23
🔬 Science Psychometrics
  1. The observed Black-White intelligence gap in standardized test performance has shown some variations over the years.
  2. Errors were found in a study that claimed a significant closure in the intelligence gap between Black and White individuals.
  3. Recent data and analyses suggest that the racial intelligence gap in the U.S. has not significantly closed and remains consistent with historical observations.

Standardized usability questionnaires: post-task measures

UX Psychology • 59 implied HN points • 23 Dec 21
🕹 Technology Psychometrics
  1. Post-task questionnaires capture user impressions immediately after a task, offering insights into user experience.
  2. Popular post-task questionnaires include the After-Scenario Questionnaire (ASQ), Subjective Mental Effort Question (SMEQ), and Expectation ratings (ER), each providing valuable usability feedback.
  3. When conducting usability studies, using multiple post-task questionnaires, like ASQ and SEQ, is recommended for a better understanding of user perceptions.