Frankfurt, Vienna, and Warsaw. We examine causal links between returns, volatility, and trading volume as well as the time of …

research on this hypothesis to open-market share repurchases. Empirical tests showed that the implied volatility spread was not … implied volatility spread and subsequent stock return volatility around open-market share repurchase events. We concluded that … option traders have private information on the volatility of stock returns and superior information processing ability that …