Scott discusses how new schizophrenia genetics research confirms that psychiatric conditions combine both 'tradeoff' components (with compensating advantages) and 'failure' components (purely negative), then argues this pattern is common sense for any multifactorial problem. Longer summary

Scott discusses new research on schizophrenia genetics which found two distinct components: one shared with bipolar that increases educational attainment (a tradeoff), and one that decreases IQ (a pure failure). He connects this to his 2021 post on tradeoff vs. failure models of psychiatric conditions, arguing that this pattern is actually common sense - most multifactorial problems naturally combine both types. He illustrates this with everyday examples like poverty (which can result from failures like poor health or tradeoffs like choosing to be a starving artist), relationships, and even physical illnesses like cancer. Scott concludes he has 'dissolved' what he previously saw as a mysterious fact about psychiatric conditions into something obvious: complex multidimensional problems will naturally have multiple causes falling into both the 'by choice' and 'not by choice' categories. Shorter summary

Scott examines a new genetic study on missing heritability that both hereditarians and nurturists claim vindicates their position, concluding that despite the study's advances, the fundamental debate over how heritable traits like IQ actually are remains unresolved. Longer summary

This post discusses a new genetic study that attempted to resolve the "missing heritability" debate - the gap between high heritability estimates from twin studies (50-80%) and low estimates from molecular genetic studies (10-20%). The study used whole-genome sequencing to include rare genetic variants and found they could account for about 88% of expected heritability, but the actual heritability estimates themselves were only medium (30-40%). Both hereditarians and nurturists claimed victory: hereditarians because the gap was closed (proving the genes exist), nurturists because the total heritability found was still lower than twin studies suggested. Scott examines both sides' arguments, including measurement error corrections and various confounders, and concludes that despite everyone's claims, the debate remains fundamentally unresolved as different methods continue producing different estimates with no clear explanation why. Shorter summary

Scott explores the 'missing heritability' problem in genetics, where twin studies show traits like IQ and educational attainment are highly heritable but newer genomic methods find much lower heritability, analyzing various potential explanations for this discrepancy. Longer summary

The post examines the 'missing heritability' problem in genetics, where twin studies consistently show behavioral traits like IQ and educational attainment are substantially heritable (around 40-60%), while newer genomic methods find much lower heritability (around 15-20%). Scott reviews the history of behavioral genetics research, explains various study methodologies and their potential biases, and analyzes different hypotheses for this discrepancy. He examines whether twin studies might be flawed, whether newer methods might be missing important genetic effects, and whether educational attainment might be an unusually problematic trait to study. While acknowledging remaining mysteries, he tentatively concludes that twin studies are probably largely correct and that newer methods may be missing rare variants and genetic interactions. Shorter summary

Scott Alexander examines hypergamy in modern marriages, finding educational hypergamy has reversed while income hypergamy persists, with strong class homogamy for both genders. Longer summary

Scott Alexander examines the concept of hypergamy, particularly focusing on educational and income differences in heterosexual marriages. He finds that while educational hypergamy (women marrying more educated men) has reversed due to women's increasing educational attainment, income hypergamy (women marrying higher-earning men) persists. The post explores various studies on class, income, and educational matching in marriages, discusses the role of physical attractiveness, and touches on hypergamy in same-sex relationships. Scott concludes that class homogamy is strong for both genders, with looks playing a smaller role than often assumed in mate selection. Shorter summary