مجله بررسی های حسابداری
پیاپی 15 (تابستان 1396)

The bulk of government revenue sources could be provided through tax. Tax avoidance causes the tax revenues of countries to appear less than what has been estimated. Thus, tax avoidance, the factors affecting it, and the results obtained would be considered as crucial topics in this area. This study examines the impact of tax avoidance and corporate governance on audit fees among the companies listed in Tehran stock exchange. In this paper, the multiple linear regression model was used to test the hypothesis. In addition, systematic elimination was used for sampling. Based on the results obtained from 142 companies during 2008 to 2015, there was no relationship between corporate governance and audit fees. Furthermore, there was a significant and negative relationship between tax avoidance and audit fees. Moreover, according to the results, cooperate governance showed no effect on the relationship between tax avoidance and audit fees.

In this research, the relationship between working capital accruals and volatility of stock returns in listed companies in Tehran Stock Exchange has been investigated. The sample of this research includes 156 companies admitted to Tehran Stock Exchange during the period from 1388 to 1394. A multivariate regression model was used to analyze the data and test hypotheses. The results show that volatility of stock returns has no significant effect on working capital accruals. Also, the financial distress does not have a significant effect on the relationship between volatility of stock returns and working capital accruals. But the company's operating cycle has a significant effect on the relationship between volatility of stock returns and working capital accruals. Also, the sensitivity of asset component of working capital versus debt component of working capital versus stock return volatility varies. The results of this research are similar to those of Aref et al (2016).

The presence of institutional investors in companie's governance structure and financial markets is recognized as a guarantee for protecting minority rights and also more stock liquidity. On the other hand, recent studies claim that trading cost is a key criterion of performance evaluation and has a critical role in financial markets. In the current research, the relationship between stock price and stock trading cost, as well as the moderating role of institutional investors in this relationship has been examined. Considering the data characteristics of the research, the statistical sample includes 69 firms listed in Tehran stock exchange over the period of 2006-2015. The statistical analysis included multivariate linear regression. The results indicate that there is a weak positive relationship between stock trading cost and stock price. Moreover, the presence of institutional investors leads to a decline in stock trading cost. The latter finding implies that institutional investors, due to their superior ability to access information, and also taking over the role of manager's monitoring, would reduce the stock trading costs resulting from ask-bid spread. Finally, the other result indicates that institutional investors could make negative the relationship between stock price and stock trading cost.

This study examines the relationship between social responsibility, economic performance and tax avoidance in companies listed in Tehran Stock Exchange. For this purpose, 47 companies of listed companies on the Stock Exchange during the time period from 2009 to 2014 were examined. Testing the research hypotheses showed that if a company has a social responsibility, the means of tax avoidance and economic value added will be decrease by contrast, if a company lacks social responsibility, the mean of tax avoidance and the mean of economic value added will increase. The company size has a significant impact on the level of tax avoidance and the bigger (smaller) the size of the company is, the more (the less) the level of tax avoidance will be. The company size and efficiency of assets has a significant impact on the economic value added of the companies. The variables of financial leverage and the ratio of market value to book value do not have a significant impact on tax avoidance and economic value added.

The main purpose of this study is to evaluate the impact of intellectual capital on economic growth in Iran. Detailed analysis of IC-related research, particularly research conducted in Iran, indicates lack of adequate attention to the impact of intellectual capital and its components by scholars on economic growth. Seeking to fill this research gap, this study included a population consisting of listed companies in Tehran Stock Exchange between the years 1386 and 1394. Of the population, 85 companies have been selected to test the research hypotheses. In order to measure intellectual capital, intellectual capital and value-added factors of two models of market value to book value are used. Results showed that among the components of intellectual capital (including the coefficient of physical capital, human capital factor and the coefficient of structural funds), only the changes of structural capital and economic growth indices correlate to one another. Analysis shows that the model of market value to book value and economic growth is significantly correlated.

The purpose of this research is examining the effect of life cycle on the conservative financial reporting of the companies listed on the Tehran Stock Exchange. The sample of the research consists of 1030 firm-year observations related to 103 companies listed on the Tehran Stock Exchange between the time span from 2006 to 2015. To measure life cycle, the model of Anthony and Ramesh (1992), and to measuring conservatism, Khan and Watts, (2009) model have been used. In analyzing the research hypotheses, SPSS Version 20 and Eviews Version 9 have been used. The results derived from testing the research hypotheses by using the panel data suggest that the different stages of companies’ life cycle including growth, maturity and decline have an effect on conservatism, and as a result the conservatism situation changes in the different stages of life cycle. In this way, the conservatism rate in the decline stage of life cycle is higher than the growth and maturity stages of life cycle; also, in the maturity stage, conservatism is higher than the growth stage.