Testing for market segmentation in the A and B share markets of China

Recent research has suggested that the A and B share markets of China may be informationally segmented. In this paper volatility patterns in the A and B share market are studied to establish whether volatility changes to the A and B share markets are synchronous. A consequence of new information, when investors act upon it is that volatility rises. This means that if the A and B markets are perfectly integrated volatility changes to each market would be expected to occur at the same time. However, if they are segmented there is no reason for volatility changes to occur on the same day. Using the iterative cumulative sum of squares across the different markets. Evidence is found of integration between the two A share markets but not between the A and B markets. © 2005 Taylor & Francis Group Ltd.