This Paper investigates the link between a firm’s competitive environment and the idiosyncratic volatility of its stock returns. We find that firms enjoying high market power, or established in concentrated industries, have lower idiosyncratic volatility. We posit that competition affects...

In the estimation of risk measures such as Value at Risk and Expected shortfall relatively short estimation windows are typically used rendering the estimation error a possibly non-negligible component. In this paper we build upon previous results for the Value at Risk and discuss how the...