Empirical analysis of time series of asset returns has revealed fat tails and volatility clustering which manifests itself as autocorrelations in absolute returns. We provide a quantitative measure of the well-studied phenomenon of volatility clustering in financial time series: We use the...

We study how sophisticated investors, when faced with changes in information environment, adjust their information acquisition and trading behavior, and how these changes in turn affect market efficiency. We find that, after exogenous reductions of analyst coverage due to closures of brokerage...