An empirical investigation on the existence of weak form efficiency: The case of Karachi stock exchange

Abstract

This research study focuses the existence of “weak form efficiency” in the Karachi stock exchange of Pakistan. Daily stock returns are used to check the “weak form efficiency’ in KSE covering a time period of 15 years ranges from July, 1997 to April, 2012. Kolmogrov-Smirnov (K-S) test, runs test, Unit root test Augumented Dickey Fuller test, Phillips Perron test are run to check the hypothesis. It is revealed that the KSE is not distributed normally and patterns are there in the prices so, the technical analyst can get the benefit in short run through predicting the future prices. This means that there exists some opportunity for the traders and investors to predict the upcoming stock prices of the securities, which are trading in the KSE and can earn high return and outperform the market. However, in long run scenario (in monthly data) the results are vice versa and Karachi stock exchange is a weak form efficient market.

Keywords

• Weak form efficiency
• Augumented dickey fuller
• Phillips perron
• Kolmogrov-Smirnov