this research intends to compare accounting variables in INCOME SMOOTHER and non-INCOME SMOOTHER FIRMS in Tehran Stock Exchange market. In this regard, the statistical typical companies were firstly separated to two INCOME SMOOTHER and nonINCOME SMOOTHER FIRMS and then the accounting variables were compared subject to above different groups.Six features including company’s size, personnel’s costs, debt ratio, industry, management bonus and tax as independent variables and INCOME smoothing behavior as dependent variable were examined in the research. This research has been carried out based on annual observations since 1384 to 1389 (2006-2011). Research findings show that company’s size, personnel’s costs, management bonus and tax are not effective factors on INCOME smoothing behavior of samples and also there is no meaningful difference among INCOME SMOOTHER and non-INCOME SMOOTHER FIRMS in these stated variables. Instead, debt ratio and industry variables are effective factors on INCOME smoothing behavior. It reveals that there is a meaningful difference between in INCOME SMOOTHER and non-INCOME SMOOTHER FIRMS in view point of debt ratio. In addition, the INCOME smoothing behavior of companies differs from each other.

Strong corporate governance system and high audit quality cause companies provide high quality and more transparent financial information through which information risk of creditors and investors reduces and thus may affect the company's cost of capital. Therefore, the main objective of the present study is to investigate the effect of corporate governance and audit quality on the cost of capital of listed companies in Tehran Stock Exchange. For this purpose, a sample of 840 firm-years during the years 2006-2011 was chosen to test the research hypotheses. For a more detailed study of the research subject, the sample divided into the sub- samples of FIRMS audited by auditing organization or by the other audit FIRMS of certified public accountants member, and also by large and small companies and eventually by INCOME SMOOTHER and non-SMOOTHER companies. The results from testing the research hypotheses on the total sample indicate that there is no significant relationship between the mechanisms of corporate governance and audit quality with the cost of capital. In addition, the results shown that the big size of board of director and existence of controlling shareholders in large companies can cause to reduce the cost of capital.

The main objective of this research is the investigation of earning management effect on intangible value of entity using Tobin’s Q in accepted companies in Tehran Stock Exchange for time period of 2003 to 2007. For INCOME smoothing measurement, in this research we employed Eckel model (1981) in three levels of gross INCOME, net INCOME and operating INCOME. In the research 60 companies using systematic random sampling selected and to test hypotheses we used from Pearson Correlation and T independent test. Research findings indicate no significant relationship between INCOME smoothing and intangible value using Tobin’s Q. in other words, the companies cannot produce any intangible value by INCOME smoothing and earning management. On the other hand, the results show there is no significant difference between two groups of companies with INCOME smoothing and no INCOME smoothing in intangible value.

Economically, sustainable INCOME is a key issue for governments. They try to compensate the expenses by tax revenues. This is regarded as an index of social sustainability and political security. One of the government goals is tax collection coinciding with giving services. Companies have different symmetry of time for receiving services and paying taxes at different stages of their life, Therefore, the purpose of this study is the evaluating of tax coinciding and expense matching through the life cycle of FIRMS. Data from 88 companies listed in Tehran Stock Exchange during the period 2011-2017 were used to test the hypotheses. The results show that firstly, there is a meaningful relationship between matching of INCOMEs and costs in the growth and maturity stage but it isnot found in the declining one. secondly, tax coincidance at the growth and maturity stage of the FIRMS life cycle is significantly different, but in the decline stage, no significant difference was found. Thirdly, tax coincidance of FIRMS with high matching degree in costs is more than that of the low matching degree costs. finally, tax coincidance of the FIRMS in declining stage with high matching in costs is less than that of low matching degree.

Profit smoothing can be seen as a deliberate reduction in profit fluctuations, so that the activities of the company appear to be normal. Managers are making profit smoothing to reduce this volatility. Some experts believe that investors are more willing to invest in smoothing companies and are willing to pay more for them. Researchers believe that some of the characteristics of the company influence the motivation of managers to smooth profits. This study attempts to explain the theoretical foundations of the research, the relationship between earnings smoothing and company characteristics such as earnings quality, P/E and ROE and ROTA. Check the securities. In order to investigate the relationship between earnings smoothing and firm characteristics, data related to the period 2010-2017 were collected and analyzed. Logistic regression was used to test the research hypotheses. The results show that companies with higher price to earnings (P/E) ratios have more incentive to report earnings. And companies with higher earnings quality are more motivated to report earnings smoothly. Finally, it was found that larger ROTAs had a greater incentive to report earnings.

The aim of this research is to study the effects of capital and ownership structure on FIRMS INCOME smoothing. In this study the discretionary accruals (measure of INCOME smoothing) is measured by modified model of Jones (1991). By using the Tucker and Zarowin (TZ) measure, FIRMS are separated in two groups, of higher and lower INCOME smoothing category. The population consist of all listed FIRMS in Tehran Stock Exchange. By using the elimination sampling method, 60 FIRMS listed in Tehran Stock Exchange, are selected during the years 1380 to 1387. The equality of two means test is used to test research hypothesis. The results show that short term debt-asset ratio, long term debt-asset ratio and debt-equity ratio in FIRMS with high INCOME smoothing are less than FIRMS with low INCOME smoothing and percentage of shares held by institutional investors in FIRMS with high INCOME smoothing is higher than FIRMS with low INCOME smoothing.

Stock return, firm size, earning volatility and cash flow volatility, are important variables in financial and accounting issues, which considering them can improve the quality of decisions. Therefore, this research study whether stock return in FIRMS with SMOOTHER earning significantly different from FIRMS with SMOOTHER cash flows. On the other hand, this research tests the same question, with the firm size instead of stock return. Statistical population includes FIRMS listed in Tehran Stock Exchange (TSE), which based on considered conditions, 50 FIRMS have been selected during 1999-2008. T-test has been applied for hypothesizes test. Results indicate that, there is no difference between average return of two groups of FIRMS that categorized according earning and cash flow volatilities cycle, but there isn’t difference between firm size in the two groups of FIRMS.

In this paper, we study effect of INCOME Smoothing on taxable INCOME determined by Auditing Organization and association of Certified Public Accountants in the companies admitted to Tehran Stock Exchange. companies admitted to Tehran Stock Exchange from 2005 to 2010 and are not amongst investing and banking brokers and they include 272 companies selected as statistical community and their information picked up from http: //rdis.ir and transferred to spread sheet software and by necessary calculation and on basis of Eckel index 151 companies as INCOME SMOOTHER and 121 companies as non- INCOME SMOOTHER are recognized. Therefore by spss-18 software and Correlation Coefficient Test of Pearson, Correlation Coefficient between declared profit and determined taxable INCOME for INCOME SMOOTHER and Non- INCOME SMOOTHER companies were calculated and comparing between 2 communities by Correlation Coefficient Test result did not indicate any outstanding difference between 2 Correlation Coefficient.