This paper analyzes the implications of autoregressive betas in single factor models for the statistical properties of stock returns. It is demonstrated that this assumption alone is sufficient to account for the most important stylized facts of stock returns, namely conditional...

A measurement error in beta that arises from changes in leverage during the beta estimation window contributes in explaining the size effect. Simulations of asset returns show that the magnitude of the bias in equity returns is proportional to the stock market-induced changes in leverage. We...

Researchers and practitioners employ a variety of time-series processes to forecast betas, using either short-memory models or implicitly imposing infinite memory. We find that both approaches are inadequate: beta factors show consistent long-memory properties. For the vast majority of stocks,...