The single-index market model is estimated with market returns from mutual funds. Binary variables are used to determine if the beta coefficients increase during bull markets. If the mutual fund beta coefficients increase during bull markets, for example, this increase indicates the portfolio...

Monthly returns are used to estimate the single-index market model (SIMM). Binary variables are used to determine if the alpha intercept and beta slope coefficients are stable through alternating bull markets and bear markets. The results suggest that some investment analysts have fallen into...