The document summarizes a research article that evaluates factors influencing expected stock returns. It finds that beta alone does not reliably explain average returns as the Sharpe-Lintner-Black model predicts. Instead, size and book-to-market equity best capture cross-sectional variation, with smaller stocks and those with higher book-to-market ratios tending to generate higher returns. The results hold across different time periods and robustness tests. The findings imply size and book-to-market may proxy for risk factors, allowing their use in portfolio evaluation and return projections if asset pricing is rational.