The Effect Manipulation of Firm Actual Activities on Stock Trading Cost

  The present research investigates the effect of manipulation of actual activities in a firm in order for profit management on stock trading cost. For this goal, the financial data of 66 companies listed in the Tehran Stock Exchange from2008 to 2015 were investigated. The multivariate regression model based on data panel and the fixed effect approach were used to verify the research hypothesis. The results of these research hypothesis show that all three components of manipulation of the firm's actual activities (abnormal cash flows, abnormal optional costs and abnormal production costs) have led to an increase in the Stock trading cost. The results showed that, the increase in stock trading cost is because of the intensified phenomenon of information asymmetry in the capital market by managers who mainly intend to achieve their own goals and positions. Furthermore and because of incorrect valuation of investors in the capital markets, stock trading costs resulting from the implementation of the trading increased. This indicates that the firm's actual activities manipulation could lead to symmetric effects on Stock trading cost.