Advances in Mathematical Finance and Application (AMFA)

The aim of this study is to evaluate the effect of information delay on theperformance of joint investment funds. In order to achieve the aim of thisstudy sample consisted of twenty funds in the Tehran Stock Exchange from2010 to 2014 the systematic elimination method has been adopted. In thisstudy, the linear regression test has been used in order to evaluate the researchhypothesis. Data analysis and research hypothesis testing has beendone using EVIEWS software. Findings of the research prove the effect ofinformation delay on the performance of joint investment funds.

The purpose of resent research is to analysis and compares performance evaluation models of selected investment companies in Tehran Stock Exchange Market in the field of their portfolio management. The duration of research was between years 2009-2014. Statistical society the research is consisting of all active investment companies in in Tehran Stock Exchange Market which were 30 companies. Volume of research sample is by using of omit systematic method and also is by considering time of accepting in stock consisting of 14 companies. Data of research which are done based on compare couple and also gathered by financial ratio. Analysis process technic is used for compare couple analysis and used criteria weight determine in ash analysis. For determining company's priority based on financial ratio and weights of any of these companies; grey analysis is used. In present research all of the relations are approved by gain results. The result shows that there is no significant difference between obtained rankings by using of grey Forecasting Johnson ranking; it could be claim that there is no priority between grey forecasting and Johnson ranking. Results based on ranking of tested companies showed that criteria that used in this research were in same direction with liquidity criteria, so it is a confirmation of the fact that economic and accounting criteria could be a good and appropriate base for investors in selecting portfolio; and also that used criteria in the research is very powerful criteria for companies’ performance assessment.

The ultimate goal of monetary policy is to achieve price stability and high output. In this regard, central banks usually change the interest rate, liquidity, and money base in order to apply monetary policies. The John B. Taylor rule is one of the rules known in the transmission of monetary policy.^{^[1]} Based on this rule and given the output gap and inflation gap, the central bank increases or decreases the interest rate. Using library references and theoretical foundations, the current paper employed a descriptive-analytical research method to explain the hypothesis stating, “Taylor rule can be used to redefine an optimal monetary rule in the central bank for the mechanism of the stable monetary policy in the framework of Iranian economy and the Interest-Free Banking Act (approved in 1983) to enforce monetary policy and control inflation.” According to the research results and the fact that Taylor rule was successful in some developed and developing countries, it can be redefined in the framework of the Interest-Free Banking Act of Iran. It can also be used as a highly flexible and appropriate monetary rule and a stable model for the mechanism of monetary policy and inflation control.

The purpose of this paper is to examine the impact of internal and external factors on the ratio of outstanding claims in those banks which are accepted in Tehran Stock Exchange. For this purpose, we used the data obtained from 8 banks and credit institution active in the Tehran Stock Exchange and using data regression panel.  The present survey was examined over the period 2011 till 2015. The study includes three external variables (inflation, GDP and interest rates) and two internal variables (rate of return on assets and the size of the bank). The results of the hypothesis study showed that the rate of inflation, GDP and asset returns had significant negative effect on the ratio of outstanding claims. The results also showed a positive significant impact of the interest rates on outstanding claims, but there was no evidence to prove a significant impact of the banks size on outstanding claims.

One of the reasons that companies avoid paying their taxes is that they choose to use debts for their funding. In other words, tax saving, an activity of companies to avoid taxpaying, can be used to finance corporate projects. Furthermore, since institutional owners are more inclined to supervise, they may shrink managerial behaviors to avoid taxpaying. In this study, institutional owners’ supervisory role about tax efficiency on corporate capital structure was investigated. For this purpose, a sample of 98 companies from 2005 to 2014 was selected from companies listed on Tehran Stock Exchange (TSE). Following the research conducted by Kramer, multiple linear regression based on panel data and the econometric software Eviews were used for testing the research hypotheses. The results show that tax has a negative and significant impact and institutional ownership has a positive and significant impact on capital structure. In addition, the institutional ownership in corporate companies impacts and adjusts the relationship between tax and capital structure.

The present research aims to evaluate impacts of crude oil price return index, Bloomberg Petroleum Index and Bloomberg energy index on stock market returns of 121 companies listed in Tehran stock exchange in a 10 years' period from early 2006 to April 2016. First, explanatory variables were aligned with petroleum products index mostly due to application of dollar data. Subsequently, to check variables stationary, Dickey-Fuller generalized test was considered and ARCH test was adopted to check for Heteroscedasticity in error terms and residual values. Finally, EGARCH was used to address model heteroscedasticity. The results showed that variations of Petroleum Bloomberg index, crude oil price and Bloomberg energy index could explain changes in Tehran stock exchange index returns. Any rise in oil prices increases total Stock Exchange returns. On the other hand, Stock Exchange index returns is aligned with Petroleum Bloomberg index.at the same time changes in Tehran stock exchange index returns was reversely correlated with changes in energy index return among others.

Companies must publish financial reports on time. When market information is more important and this information is used to shape more effective decision-making. Although most companies, financial reports required by the authorities at intervals determined Speak but at the same time, it can be claimed that the delay in publishing the financial reports of a company to another company, the difference is significant The statistical sample included 116 companies in Tehran Stock Exchange during the years 2010 to 2014. In this study, the hypothesis of linear regression was used Software to analyse data and test hypotheses have been used Eviews results The research suggests that the company's sales on the disclosure of bad news affects companies as well as participate in interactive sales ratio of sales to working capital, fixed assets is effective.

Profitability as the most important factor in decision-making, has always been considered by stake­holders in the company's profitability. Also can be a basis for evaluating the performance of the managers. The ability to predict the profitability can be very useful to help decision-makers. That's why one of the most important issues is the expected profitability. The importance of these forecasts depends on the amount of misalignment with reality. The amount of deviation is less than the forecast of higher accuracy. Although there are various methods for predicting but the use of artificial intelligence techniques is increasing due to fewer restriction. The aim of this study is to evaluate the predictive power of profitability using DEA and neutral network, to enhance the decision-making users of 2012 to 2015of 7 premier financial ratios were used as independent variables. Test results show that both of ANN and DEA have ability to forecast profitability and given that neutral network prediction accuracy is higher than the DEA, the model predict better the profitability of companies.