Are Gulf stock markets efficient? Evidence from new multiple variance ratio tests

Abstract

The purpose of this article is to test for the Random Walk Hypothesis (RWH) for seven stock markets in Gulf Cooperation Council (GCC) countries, and to determine the effect of the correction for thin trading. Three new multiple variance ratio tests are applied to both observed returns and returns corrected for thin trading. It is found overall that the RWH does not hold for the GCC stock markets at both daily and weekly frequencies. This evidence is particularly strong when daily returns are used, where the RWH is soundly rejected for both observed and corrected returns.