Academic reference · Idiosyncratic Risk and Active Share
Ang et al. (2006)
Ang, A., Hodrick, R. J., Xing, Y., & Zhang, X. (2006). The cross-section of volatility and expected returns. Journal of Finance, 61(1), 259–299.
Why it matters
Shows that idiosyncratic volatility is empirically important and not safely ignored in expected-return or risk analysis.