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Next filing · Form 10-Q · Q2 2026 · 37 daysMethodology Paper · Part III published: The One Manager Skill That PersistsAPI Update · Point-in-Time (PIT) historical commit tracking — securities and funds unifiedAPI Update · ERM3 L3 variance partition — institutional transparency releasePart 3 · The Persistence of Stock-Selection ResidualsPart 1 · One Position, Four BetsNext filing · Form 10-Q · Q2 2026 · 37 daysMethodology Paper · Part III published: The One Manager Skill That PersistsAPI Update · Point-in-Time (PIT) historical commit tracking — securities and funds unifiedAPI Update · ERM3 L3 variance partition — institutional transparency releasePart 3 · The Persistence of Stock-Selection ResidualsPart 1 · One Position, Four Bets
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Academic reference · Idiosyncratic Risk and Active Share

Roll (1988)

Roll, R. (1988). R². Journal of Finance, 43(3), 541–566.

Why it matters

Highlights how much firm-level variation remains unexplained by common factors, directly motivating residual-risk diagnostics.

Read at publisher ↗All references
← Ang et al. (2006)Idiosyncratic Risk and Active Share · 3 / 3Cremers et al. (2009) →
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