Idiosyncratic Volatility and the Cross-Section of Anomaly Returns : Is Risk Your Ally?

Due to arbitrage risk asymmetries, the relationship between idiosyncratic risk and expected returns is positive (negative) among overpriced (underpriced) stocks. We offer a new active anomaly-selection strategy that capitalizes on this effect. To this end, we consider eleven equity anomalies in the U.S. market for years 1963-2016. Buying (selling) long (short) legs of the anomaly portfolios with the highest idiosyncratic volatility produces monthly abnormal returns ranging from 0.97% to 1.14% per month, outperforming a naive benchmark that equally weights all the anomalies by 45-70%. The effect cannot be subsumed by any other established anomaly-return predictor, like momentum or seasonality. The results are robust to many considerations, including different numbers of anomalies in the portfolios, subperiod analysis, as well as estimation of idiosyncratic risk from the alternative models and throughout different periods