We develop a simulation-based procedure to test for stock return predictability with multiple regressors. The process governing the regressors is left completely free and the test procedure remains valid in small samples even in the presence of non-normalities and GARCH-type effects in the stock...

Hundreds of papers and hundreds of factors attempt to explain the cross-section of expected returns. Given this extensive data mining, it does not make any economic or statistical sense to use the usual significance criteria for a newly discovered factor, e.g., a t-ratio greater than 2.0....

In the three-factor model of Fama and French (1993), portfolio returns are explained by the factors Small Minus Big (SMB and High Minus Low (HML) which capture returns related to firm capitalization (size) and the book-to-market ratio (B/M). In the standard approach of the model, both the test...