Mostafa bakhtiari - Ph.D. Candidate, Department of Financial Management, Science and Research Branch, Islamic Azad University, Tehran, Iran
Hashem Nikoomaram - Faculty Member, Department of Financial Management, Science and Research Branch, Islamic Azad University, Tehran, Iran
Fereydon Rahnamay Roodposhti - Faculty Member, Department of Financial Management, Science and Research Branch, Islamic Azad University, Tehran, Iran
Taghi Torabi - Associate Professor, Faculty of Management and Economics, Islamic Azad University, Science and Research Branch, Iran

In Recent Decades, The Financial Sphere has entered a New Era of Contempt for Some of the Assumptions of Modern Economics and Finance. One of These Assumptions is the Rationale of the Investors, which has been Seriously Challenged and Is Now Being Strengthened by the Fact That Prices are Determined more by Attitudes and Psychological Factors than for Fundamental Variables and Therefore the Study of Market Psychology has Become More Important. The Purpose of This Research is to assess the Reaction of Investors to Price Changes by Measuring the Speed of Price Adjustment Compared to the General Information in Tehran Stock Exchange and a Model for Yielding Additional Returns in Futures. The five-year Research Period is from ۲۰۱۱ to ۲۰۱۶. The Statistical Population of the Study is the Companies listed in Tehran Stock Exchange and the Results Show that the Rate of Adjustment of Prices is Different from Each other Based on Specific Company Variables, and the Difference in the Rate of Price Adjustment can Cause Make Extra Returns.

Speed of Price Adjustment, Excess Return, Over Reaction, Under Reaction