The Hierarchy of Effective Factors on Corporate Tax Avoidance Because of the information asymmetry within taxpayers and governments, commonly, the taxpayers try avoid the payment of tax. The problem can be explained by Agency theory. On the other hand, governmants try to maximize receiving tax by recognizing risky taxpayers and researchers try to recognize effective factors on tax avoidance. The aim of the research is the hierarchy of effective factors on corporate tax avoidance on Tehran stock exchange. In this research, first, 37 quantity factors are recognized that affect on corporate tax avoidance in 8 dimensions by interview with academic and professional experts that can be measure by corporate reports.
   Then the factors and dependent variable are measured and are tested the efficacy of the dimensions by structural equation model (SEM). Finally, based on confirmed dimensions, hierarcy is done by contributed analytic hierarchy process quastionaries with same experts. Statistic population in this research involves 77 companies listed in Tehran Stock Exchange during the period 2013-2017 that are selected by systematic delete. The interview with experts done at 2017 and questionaries contributed at 2018. Results show that the hierarchy of effective factors on corporate tax avoidance is: trading factors, corporate governance factors, auditor factors, financial reporting factors, industrial factors, public attributes, capital market factors and social factors.

Companies ability during Crisis has been evaluated. Considering the fact that economic crisis comes along with uncertainty and fluctuations in macroeconomic variables and it causes in a special situation in the economic circumstance of the country and companies activities in that, therefore it can affect the ability and the power of management on the company’s performance and its value. So in this research behavioral features including; social responsibility reporting ,agency cost and tax avoidance in financial crisis have all been incorporated. Therefore, this study used behavioral characteristics including social responsibility reporting, agency costs, and tax avoidance in times of economic crisis. Accordingly, the data of 197 listed companies in Tehran Stock Exchange for the years 2006-2017 is analyzed. The results of the study show the behavioral characteristics of the company,  social responsibility reporting by decreasing the negative effect of economic crisis creates a positive effect of power and management ability on its value and financial performance. In addition, the results indicate that the higher agency cost of the company by increasing the negative impact of economic crisis will have a more negative effect on the strength and ability to manage its value and financial performance. On the other hand, the results indicate that the tax avoidance characteristics does not play a significant role in the adjustment of the economic crisis on the relationship between management power, company value and financial performance. Overall this research proves that the behavioral characteristics of a company can decrease the effect of economic crisis on the relationship between CEO power and firm value and financial performance.