Relationship between Trading Volume and Asymmetric Volatility in the Korean Stock Market

We investigated the relationship between return volatility and trading volume as a proxy for the arrival of information to the market, based on Korean stock market (KSM) data from January 2000 to December 2010. We measured the rela- tionship between return volatility and trading volume using the GJR-GARCH and exponential GARCH (EGARCH) models. We found a positive relationship between trading volume and volatility, suggesting that trading volume influ- ences the flow of information to the market. This finding supports the validity of the mixture of distributions hy-pothesis. Considering that trading volume can also explain volatility asymmetry, we conclude that trading volume is a useful tool for predicting the volatility dynamics of the KSM.