Characteristics, covariances, and structural breaks

By applying Bai and Perron's [Bai, J., Perran, P., 1998. Estimating and testing linear models with multiple structural changes. Econometrica 66, 47-78] change-point model, we pinpoint the exact dates for structural breaks in the book-to-market premium. We find that overall the BM premium is better explained by Fama-French's three-factor model.