What can explain this disparity? One possible explanation is that the performance differences are driven by differences in the riskiness or "style" of the two portfolios. Researchers have identified several equity characteristics that explain differences in realized returns. In addition to differences in exposure to the market factor ("beta"), a firm's market capitalization (or "size"), book-to-market ratio (or other "value" characteristics), and immediate past returns ("momentum") have all been shown to significantly forecast future returns.16 If the Dictatorship Portfolio differs significantly from the Democracy Portfolio in these