Effect of over time on Unusual fluctuations on stock returns of companies listed in Tehran Stock Exchange

Abstract

Objective: Finance reporting with quality and clear finance statement could eventuate to important economic results such as reduction in vibrancy of anomaly stock output. In other words, how much the finance statement of companies, specially reported profit by firms, be more quality; based on efficient market theory, it is expected this information peers in stock price, so price of stock will have less vibrancy. Methodology: In this research is evaluated about impact of finance reporting quality and time passage on output of anomaly stock in accepted companies in Tehran Stock Exchange for five years period (between 2009 to 2013). Results: In this study are used from two models of Dechow and Francis for measurement the finance reporting quality and time passage. Also, in this research linear regression is used for data analysis. Conclusion: This study is application type and also in terms of inference is description-analytical (apriority) and in terms of research plan is scientific. Variables of time (T); variable of book value to market value (BM) with significant level of less than 0.05 have significant impact on relative variable. Variables of yearly stock output (RET) with significant level of more than 0.05 have no significant impact on relative variable, so these variables have no significant impact on anomaly vibrancy of stock output.