A number of studies have identifed patterns of positive correlation of returns, or comovement, among different traded securities. We distinguish three views of such comovement. The traditional 'fundamentals' view explains the comovement of securities through positive correlations in the rational...

This paper uses a new data set of quarterly portfolio holdings of 769 all-equity pension funds between 1985 and 1989 to evaluate the potential effect of their trading on stock prices. We address two aspects of trading by money managers: herding, which refers to buying (selling) the same stocks...

From 1963 through 2015, idiosyncratic risk (IR) is high when market risk (MR) is high. We show that the positive relation between IR and MR is highly stable through time and is robust across exchanges, firm size, liquidity, and market-to-book groupings. Though stock liquidity affects the...

Using theories from the behavioral finance literature to predict that investors are attracted to industries with more salient outcomes and that therefore firms in such industries have higher valuations, we find that firms in industries that have high industry-level dispersion of profitability...

We analyze time-series of investor expectations of future stock market returns from six data sources between 1963 and 2011. The six measures of expectations are highly positively correlated with each other, as well as with past stock returns and with the level of the stock market. However,...