A five-factor model directed at capturing the size, value, profitability, and investmentpatterns in average stock returns performs better than the three-factor model of Fama andFrench (FF, 1993). The five-factor model's main problem is its failure to capture the lowaverage returns on small stocks whose returns behave like those of firms that invest a lotdespite low profitability. The model's performance is not sensitive to the way its factorsare defined. With the addition of profitability and investment factors, the value factor ofthe FF three-factor model becomes redundant for describing average returns in thesample we examine.