We derive a nonparametric test for constant (continuous) beta over a fixed interval of time. Continuous beta is defined as the ratio of the continuous covariation between an asset and observable risk factor (e.g., the market return) and the continuous variation of the latter. Our test is based...

Reliably estimating the beta of an individual stock has proved elusive. Individual stock price movements are a function of market/systematic movements and company specific/idiosyncratic movements. Since traditional beta estimation calculations make no attempt to minimize the impact of the...

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...