Equilibrium Asset Pricing Under Heterogeneous Information

Abstract

We analyze theoretically and empirically the implications of heterogeneous information for equilibrium asset pricing and portfolio choice. Our theoretical framework, directly inspired by Admati (1985), implies that with partial information aggregation, portfolio separation fails, buy-and-hold strategies are not optimal, and investors should structure their portfolios using the information contained in prices in order to cope with winner's curse problems. We implement empirically such a price-contingent portfolio allocation strategy and show that it outperforms economically and statistically the passive/indexing buy-and-hold strategy. We thus demonstrate that prices reveal information, in contrast with the homogeneous information CAPM, but only partially, consistent with a Noisy Rational Expectations Equilibrium. The success of our pricecontingent strategy does not proxy for the success of trading strategies based purely on historical performance, such as momentum investment.