Investigation of Effect of Information Content Net Earnings on the Stock Price Changes (Case Study of Tehran Stock Exchange)

This paper has studied change of stock prices toward actualnet earnings and predicted net earnings announcement in tehran stockexchange. for analyzing hypotheses, stock price changes were studiedin two dates of actual net earnings and predicted net earnings announcementand also one month after that date. statistical populationof research included companies that their stocks were traded actively intehran stock exchange during annual period of 2011. two hypothesesof research were analyzed by sign test and chi2- test. the resultsshow that in announcement day of actual net earnings and predictednet earnings, there is a significant relationship that include informationcontent of predicted net earnings between observed frequencies in pricechange.