Résumé en anglais

This article focuses on the impact of derivative markets on the American crude oil market. It first analyses the depth and liquidity of the market, and shows that there is a huge increase in activity from 1989 to 2003. Then the study focuses on prices volatility. The latter is separated into two components: an information component, that reflects a rational assessment of the information arrival, and an error component, that represents the noise introduced by the trading process. We show that a significant part of the volatility recorded during exchange trading hours is due to mispricing errors.