This paper proposes a novel standardized test for abnormal returns in long-horizon event studies that takes into account cross-sectional correlation, autocorrelation, and hetersoskedasticity of stock returns. Extensive simulation analyses demonstrate improved size and power of testing relative...

The informed options trading hypothesis posits that option prices lead stock prices. In this paper, we extended the research on this hypothesis to open-market share repurchases. Empirical tests showed that the implied volatility spread was not significantly related to buy-and-hold abnormal stock...

Momentum profits collapse and reversal occurs when preceding market volatility is relatively high. Based on these intertemporal patterns, we implement an investment strategy that switches from momentum to reversal when volatility is high. The proposed switching strategy has two advantages over...