What is Adjusted Returns

This study has two important findings firstly, the theoretical results related to the efficient market hypothesis; and secondly, the results of application. The theoretical results show that if the market price of an asset includes all the information that influences its price, then that market is an efficient market. According to the efficient market hypothesis, investors cannot earn gains above the market return. Since stock share prices are unpredictable, it is assumed that when the information that the market had already been expecting is finally announced, the stock share prices will not change. That is because this announcement does not contain any information that can change the prices. The results obtained from the application show that the existence of abnormal return is valid for Islamic Stock Markets. Therefore, the findings mediate against the efficient market hypothesis. However, when the size of abnormal returns is observed, the results are almost equal to market returns. This finding supports the efficient market hypothesis. Islamic stock markets are integrated with the world at least as much as the non-Islamic global markets are. Islamic stock markets act together with the non-Islamic global markets. The risks and returns that the Islamic and non-Islamic stock markets provide to the investors are very close to each other. In conclusion, the efficient market hypothesis maintains its explanatory power for both Islamic stock markets and non-Islamic global stock markets. Islamic markets offer new investment opportunities on a global scale.