نویسنده
چکیده
کلیدواژهها
عنوان مقاله [English]
Stock exchange is a market that suppliers and companies present their stocks and securities for sale, also investors come to buy these securities. With due attention to information that is very important for efficiency of stock market, market efficiency was studied by three groups of information. This information consists of:
1) Historical information
2) The current or general available information
3) General and inside information
With due attention to such information, market efficiency is tested in three levels respectively: weak, semi-strong and strong form. The main purpose of this research is to study the efficiency of stock market in the weak level to answer the question "are respectively changes of stock prices independent from each other?" In this study, the statistical methods, correlation analysis which is a parametric method and Run-test that is a non parametric method are used. The data in this study is the stock daily price for ninety five accepted companies in the stock exchange between 1999 and 2006. The results showed that, there is a correlation between the respectively changes of stock prices in 95% of confidence level, and particular investors can gain irregular profit by having some inside information .Generally, inefficiency of the information of Tehran stock exchange is proved
کلیدواژهها [English]
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