This article examines the informational quality of implied volatility in forecasting future realized volatility using daily S&P 500 and S&P 100 index option prices from 2000 to 2006. In contrast to many previous studies, we find that implied volatility is an unbiased and efficient estimator of...

Using a vector autoregressive (VAR) approach, the dynamic interactions and causal relationships among volatility, open interest, trading volume and arbitrage opportunities in the S&P 500 index futures market is examined. It is found that increased volatility lowers pricing error. This implies...