Mutual fund performance persistence: Factor models and portfolio size

We re-examine US mutual fund performance persistence. We investigate persistence (i) using both "academic" factor models and "practitioner" index models, (ii) using decile-size recursive portfolios and also portfolios formed from smaller numbers of funds, (iii) using nonparametric bootstrap p-values as well as conventional t-tests and (iv) using both net-of-fee fund returns (net alphas) and gross alphas. Our key result is that positive net alpha performance persistence can be found using small portfolios of funds together with a holding period of 6 months or less, for both practitioner index models and academic factor models.