Long/short equity hedge funds and systematic ambiguity

This study presents a hedge fund portfolio choice model for an investor facing ambiguity. In the empirical section, we measure ambiguity as the cross-sectional dispersion in Industrial Production growth and in stock market return forecasts, and we construct the systematic ambiguity factors from the universe of S&P 500 stocks. We estimate ambiguity betas for long/short equity hedge funds strategies and document signi cant ambiguity exposures for directional L/S equity hedge funds. We compare the out-of-sample performance of portfolios constructed according to the L/S hedge fund alphas' ranking with and without systematic ambiguity exposures and nd that the former outperform