We demonstrate that the estimates of the Capital Asset Pricing Model (CAPM) parameters significantly differ across samples, which are based on different days of the week (representing different seasons). Our evidence suggests that the “noise” in the data is not an issue. We also show that...

This paper demonstrates that the factors based on typical procedures that employ sorting by characteristics (including size and book-to-market, among others) can create a good mechanical fit in the regressions of portfolio returns. Such factors are approximately linear functions of the sorted...

We show that in the presence of non-zero pricing errors, the Fama–MacBeth (FM) cross-sectional regression test is very likely to either reject the Capital Asset Pricing Model (CAPM) when it (almost) holds or accept the model when it grossly fails. We investigate the case when pricing errors...

We investigate the relationship between changing correlation structure of returns, security risk, and mean return. According to our results, securities that were highly correlated with the market-wide risk factors in the past are likely to have high systematic and idiosyncratic risk at present....

We investigate a link between the performance of several security indexes in broad investment categories and investor attention as measured by Google search probability. We find that there is a significant short-term change in index returns following an increase in attention. Conversely, a shock...

This paper investigates change in idiosyncratic volatility estimated by individual security. We find that a significant portion of securities contains long periods of increasing or decreasing idiosyncratic risk. The series of idiosyncratic risk though are unlikely to have a life-long...

We investigate the effects of several firm characteristics utilized in the recent literature to account for puzzling dynamics of idiosyncratic risk. Our results suggest that these characteristics (book-to-market, leverage, size, institutional ownership, earnings-per-share, and turnover) are able...