The relationship between asset demand and information quality in rational expectations economies is analyzed. First we derive a number of new summary descriptive statistics that measure four basic characteristics of investment style: asset selection, market timing, aggressiveness, and specialization. Then we relate these statistics to the divergence between a given investor's information structure and the market average information structure. Finally, we demonstrate that informational differentials can be identified, and consistently estimated, using ordinary least squares, from the time-series of observed asset demand.

We present an economic mechanism and supportive empirical evidence for the transmission of information between equity securities first documented by Lo and MacKinlay (1990). It is argued that the past returns on stocks held by informed institutional traders will be positively correlated with the contemporaneous returns on stocks held by noninstitutional uninformed traders. Evidence consistent with this hypothesis is then presented. We document that the returns on the portfolio of stocks with the highest level of institutional ownership lead the returns on portfolios of stocks with lower levels of institutional ownership. This effect persists even after firm size is controlled for and is apparent at longer lags than the size-related lag effects documented in Lo and MacKinlay (1990).