The on-going debate over whether fund managers have skills and whether those skills are short-lived is still inconclusive. Using the performance measure that can't be manipulated with respect to the underlying distribution, time variation, nor estimation error, (the manipulation-proof...

This paper develops a dynamic model of asset price behavior based upon the arrival and diffusion of rumors in a securities market. The model is based upon a time-homogeneous pure birth process in which the number of informed and uninformed traders varies probabilistically over time as learning...

We address implementation issues related to Wald tests associated with mean-variance spanning when short positions in portfolios are prohibited. In particular, we exploit the uniqueness of the stochastic discount factor in the presence of a risk-free rate to avoid potential numerical stability...

Previous studies have focused on which stocks are winners or losers but have paid little attention to the formation process of past returns. This paper develops a model showing that past returns and the formation process of past returns have a joint effect on future expected returns. The...