We study return predictability using a model of speculative trading among relatively overconfident competitive traders who agree to disagree about the precision of their private information. Although traders apply Bayes Law consistently, returns are predictable. In addition to trading on...

Through extending a standard Grossman and Stiglitz (1980) noisy rational expectations economy by a heterogeneous signal structure with signal-specific differences in uncertainty, we show that price momentum as well as reversal are not intrinsically at odds with rational behavior. Differences in...