We investigate the relative importance of various factors in explaining the volatility skew observed in the prices of stock options traded on the Chicago Board Options Exchange. The skewness of the risk-neutral density implied by individual stock option prices tends to be more negative for stocks that have larger betas, suggesting that market risk is important in pricing individual stock options. Also, implied skewness tends to be more negative in periods of high market volatility, and when the risk-neutral density for index options is more negatively skewed. Other firm-specific factors, including firm size and trading volume a so help explain cross-sectional variation in skewness. However, we find no robust relationship between skewness and the firm's leverage. Nor do we find evidence that skewness is related to the put/call ratio, which may be viewed as a proxy for trading pressure or market sentiment. Overall, firm-specific factors seem to be more important than systematic factors in explaining the variation in the skew for individual firms.

Abstract We study the dynamic relation between daily stock returns and daily innovations in optionderived implied volatilities. By simultaneously analyzing innovations in index- and firmlevel implied volatilities, we distinguish between innovations in systematic and idiosyncratic volatility in an effort to better understand the asymmetric volatility phenomenon. Our results indicate that the relation between stock returns and innovations in systematic volatility (idiosyncratic volatility) is substantially negative (near zero). These results suggest that asymmetric volatility is primarily attributed to systematic market-wide factors rather than aggregated firm-level effects. We also present evidence that supports our assumption that innovations in implied volatility are good proxies for innovations in expected stock volatility.

ABSTRACT We investigate the relationship between the ownership structure and returns of firms on days when the absolute value of the market's return is two percent or more. We find that a firm's abnormal return on these days is related to the percentage of institutional ownership, that there is abnormally high turnover in the firm's shares on these days, and that this abnormal turnover is significantly related to the percentage of institutional ownership in the firm. Taken together, these results are consistent with positive feedback herding behavior on the part of some institutions, particularly mutual and pension funds.

Is liquidity better when a trade counterparty’s brokerage firm is unknown (anonymous) or known (transparent)? We examine a quasinatural experiment where some firms switched from transparent to anonymous trading and then, 1 year later, switched back. Our results for inside spread, price impact, and limit order book depth suggest that liquidity improves when anonymous post-trade reporting is introduced and liquidity worsens when anonymous post-trade reporting is reversed.

Dividends are clustered in increments of 5, such as 25, 50, and 75. Firms that gravitate towards these ‘prominent’ amounts have lower operating performance and lower annual five-factor alphas of 77 b.p. Consistent with agency frictions that lead to lazy decisions, clustering effects are stronger for entrenched firms, with more market power, and less shareholder activism. Dividend increases also cluster more than cuts, consistent with saliency bias. In a counterfactual exercise, we find no similar patterns in a sample of ADRs. Our results complement a number of recent studies showing the economic importance of simple decision heuristics.

ABSTRACT Institutions often own equity in multiple firms that compete in the same product market. Prior research has shown that these institutional “common owners” induce anticompetitive pricing behavior in the airline industry. This paper reevaluates this evidence and shows that the documented positive correlation between common ownership and airline ticket prices stems from the market share component of the common ownership measure, and not the ownership and control components. We further show that the results are sensitive to measures of investor control and to assumptions about equity holders' ownership and control during bankruptcy.