ABSTRACT Short‐sales practices in the Hong Kong stock market are unique in that only stocks on a list of designated securities can be sold short. By analyzing the price effects following the addition of individual stocks to the list, we find that short‐sales constraints tend to cause stock overvaluation and that the overvaluation effect is more dramatic for individual stocks for which wider dispersion of investor opinions exists. These findings are consistent with Miller's (1977) intuition and other optimism models. We also document higher volatility and less positive skewness of individual stock returns when short sales are allowed.

We study the dynamic relation between aggregate mutual fund flow and market-wide volatility. Using daily flow data and a VAR approach, we find that market volatility is negatively related to concurrent and lagged flow. A structural VAR impulse response analysis suggests that shock in flow has a negative impact on market volatility: An inflow (outflow) shock predicts a decline (an increase) in volatility. From the perspective of volatility–flow relation, we find evidence of volatility timing for recent period of 1998–2003. Finally, we document a differential impact of daily inflow versus outflow on intraday volatility. The relation between intraday volatility and inflow (outflow) becomes weaker (stronger) from morning to afternoon.

Abstract A three parameter stochastic process, termed the variance gamma process, that generalizes Brownian motion is developed as a model for the dynamics of log stock prices. Theprocess is obtained by evaluating Brownian motion with drift at a random time given by a gamma process. The two additional parameters are the drift of the Brownian motion and the volatility of the time change. These additional parameters provide control over the skewness and kurtosis of the return distribution. Closed forms are obtained for the return density and the prices of European options.The statistical and risk neutral densities are estimated for data on the S&P500 Index and the prices of options on this Index. It is observed that the statistical density is symmetric with some kurtosis, while the risk neutral density is negatively skewed with a larger kurtosis. The additional parameters also correct for pricing biases of the Black Scholes model that is a parametric special case of the option pricing model developed here.

Abstract The suitability of complex financial products for household investors is an important issue in light of consumer financial protection. The U.S. Dodd–Frank Act, for instance, mandates that distributors check suitability when selling structured products to retail investors. However, little empirical evidence exists on such transactions. Using data from Hong Kong, we find that investors purchase 8% more structured products, on average, when the suitability is not checked. The effect of suitability checks is more pronounced for less financially literate investors. Moreover, investors tend to buy products with lower risk-adjusted returns when product suitability is not checked.

We explore the governance effect of short-selling threat on mergers and acquisitions (M&A). We use equity lending supply (LS) to proxy for the threat, as short sellers incentives to scrutinize a firm depend on the availability of borrowing shares. Our results show that acquirers with higher LS have higher announcement returns. The effect is stronger when acquirers are more likely to be targets of subsequent hostile takeovers and when their managers wealth is more linked to stock prices. We conduct four sets of tests to mitigate endogeneity concerns. Finally, the governance effect exists only for deals prone to agency problems.

We use data uniquely available from the Commodity Futures Trading Commission (CFTC) to document the intraweek trading patterns of large speculators in five futures markets. These markets include futures traded against the Standard and Poor's 500 stock index, Treasury Bonds, gold, corn, and soybeans. We also examine the influence of large speculator trades on the patterns of volume and volatility for the contracts in our sample. Though we detect the familiar U-shaped and inverted U-shaped patterns across weekdays for volatility and aggregate volume, the association between volume and volatility becomes stronger when we separate large speculator volume from volume associated with other traders. The coefficient on large speculator volume is much larger than the coefficient on other volume in these regressions. Compared with total volume, large speculator volume is greater on Mondays than on the other days of the week in all five markets.

We examine the relationship between Chief Executive Officer (CEO) turnover and the performance of listed Chinese firms and obtain two results. First, we find a negative relationship between the level of pre-turnover profitability and CEO turnover when firms are incurring financial losses, but no such relationship when they are making profits. Second, there is an improvement in post-turnover profitability in loss-making firms, but no such improvement in profit-making firms. These results indicate the existence of a time-varying objective function, whereby shareholders have a greater incentive to discipline their CEOs on the basis of financial performance when their firms are incurring financial losses rather than profits.

We identify an important channel, acquisitions of public targets, via which the governance through trading (GTT) improves firm values. The disciplinary effect of GTT is more pronounced for firms with higher managerial wealth-performance sensitivity and moderate institutional ownership concentration. Firms with higher GTT also have higher subsequent ROA, ROE, Tobin's Q, analysts forecasted EPS growth rate, and lower expected default risk. The effect is stronger after Decimalization. We conduct several exercises to rule out alternative explanations, such as institutional superior information, investor activism, and momentum. Additional tests show that the disciplinary effect of GTT only exists for less financially-constrained firms and non-all-cash M&As where the agency problem is more likely to be prevalent.

China launched a pilot scheme in March 2010 to lift the ban on short-selling and margin-trading for stocks on a designated list. We find that stocks experience negative returns when added to the list. After the ban is lifted, price efficiency increases while stock return volatility decreases. Panel data regressions reveal that intensified short-selling activities are associated with improved price efficiency. Short-sellers trade to eliminate overpricing by selling stocks with higher contemporaneous returns following a downward trend, and their trades predict future returns. In contrast, we find intensified margin-trading activities for stocks with lower contemporaneous returns, and these trades have no return predictive power.

We measure an individual stock’s misvaluation based on the deviation of its price from predicted intrinsic value. Both under- and overvalued stocks identified by this misvaluation measure exhibit greater valuation uncertainty and arbitrage difficulty, and the misvaluation measure strongly predicts stock returns incremental to size, book-to-market ratio, past returns, and various return anomalies. Based on the misvaluation measure, we form a misvaluation factor and find that stock return covariances with this factor possess significant and robust return predictive power. We further show that the misvaluation factor predicts future economic conditions, providing additional insight into the real effect of systematic misvaluation in the stock market.