فصلنامه دانش مالی تحلیل اوراق بهادار
سال سیزدهم شماره 45 (بهار 1399)

The purpose of this paper is to investigate the effect of credit and non-liquidity andmarket risks on the financial efficiency in the 102 Tehran Stock Exchange companiesduring 2011-2016. We use Amihud ratio to calculate the non-liquidity risk, the Creditrating was used with the Topsis model and CVaR was used for market risk. In order to weuse the return-on-equity (book value) ratio, the return-on-equity (market value) ratio andmarket value added, while analyzing the impact of financial risks on them with the GMMgeneralized regression model, the ability to explain each one and determine which is abetter benchmark for efficiency explanation. According to the results, there is nomeaningful relationship between all three risks with the return-on-equity (book value)ratio, while the effect of these risks with the return-on-equity (market value) and marketvalue added ratio are significant, which is the ability to explain the return-on-equity(market value) More than market value added

The stock price crash is associated with profitability as the most important goal of investing. The effective role of stock price crash in reducing the capital of investors is of great importance for identifying and detection an abnormal trend in stock returns and stock price crash. The purpose of this study is to detect abnormal returns and ultimately the crash of stock price. For this purpose, the monthly returns of 400 companies admitted to Tehran Stock Exchange during the period of July 1992 to April 2018 were investigated. Also, memory-based graph theory is used as a way to detect changes in the corporate returns. This algorithm approaches the problem from a graph-theoretic perspective. The results of this study have shown that memory-based graph theory leads to identifying abnormal changes in the corporate returns. However, this method has not been able to identify and detect all the points associated with crash of stock price.

Investment decision making is one of the key issues in financial management. Investor might know about different asset types when facing with various options and the ways in which investors can incorporate them in devising a strategy is significant. Selecting the appropriate tools and techniques that can make optimum portfolio is one of the main objectives of the investment world. In this study it is tried to optimize the decision making in stock selection or optimization of portfolio by means of artificial colony of honeybee algorithm. And to determine the effectiveness of the algorithm, Sharp criteria algorithm, the trainer criteria and its downside risk were calculated and compared with the portfolio made up of genetic and ant colony algorithms .The sample consisted of active firms listed in the Tehran Stock Exchange from 2005 to 2015. The sample was selected by the systematic removal method. The findings show that Sharp criteria algorithm formed by the artificial bee colony algorithm functions better than the genetic and ant colony algorithms in terms of portfolio formation .However, the trainer's criteria and downside risk of the stock portfolio formed through the artificial bee colony algorithm shows the optimum function, this difference is not statistically significant.

Following the horrific events and crises that took place in the world's stock exchanges, especially in September 1997, and then the disclosure of Worldcom, Enron, Xerox and Parmalat in the world, and the collapse of the Tehran Stock Exchange in 2004, the issue of transparency of financial statements The title of a phenomenon is of great importance. Therefore, the present study examines the effect of financial decentralization on the relationship between financial leverage and cautious financial reporting in companies admitted to Tehran Stock Exchange. To do this research, information Related to the research literature using the library research method and the use of various copper papers Pinch of Web sites collected and used. To test the hypotheses of this research, 119companies were utilized during 2011-2011. Initially, the research variables were identified and the required information related to financial statements was extracted from the Stock Exchange web-sites and in the extended section of the excel class These data were tested to test the hypotheses and research models that were estimated by panel data using SPSS 19 and Eviews 1software. The results of this study indicate that between financial leverage and financially sound reporting in companies Accepted in Tehran Stock Exchange has a direct and significant relationship D.hmchnyn fiscal decentralization on the relationship between financial leverage and aggressive financial reporting of listed companies in Tehran Stock Exchange is not affected.

A retired person faces two major risks: life-long risk and investment risk. In this paper, we examine the effect of decision-making policy on the amount of defaults by using two objective functions for wealth at retirement time. The expressed policies relate to the return on target markets for investment and the discount rate in the economy. In the modeling of these policies, a dynamic programming approach combined with historical simulation has been used. The results indicate the importance of selecting the objective function. Given the severe economic fluctuations in the country, as well as the need for greater wealth accumulation and greater participation in controlling economic fluctuations, the policy of focusing on pension with the lower wealth in retirement period as an optimal policy - because of the acceptance of lower risk for a certain level of wealth - and more use of the wealth function during retirement time is suggested.

In this paper, for the first time ,calculation of optimal hedge ratio for future gold coin contracts has been conflated a multivariate GARCH model (dynamic conditional correlation) with Markov Switching (MS).To this end, we use spot and futures daily prices over the 2017 March through 2018 March in Iran.The results of the Markov regime switching model indicate that the study period is identified under two regimes, which is a regime that reflects the low correlation regime of the futures market and other regime indicating a high correlation on the future market. Furthermore, the optimal hedge ratio of futures contracts are less than 1 and it means the cost of this strategy is less than simple hedge ratio. In general, it can be said that a higher risk prediction under the influence of bad news leads to a transition to a high correlation regime, with the relief of uncertainty, it will be shifted in other regime. In the Economic Analysis of Extreme points of the time series of optimal hedge ratios, results show that among the major fluctuations, the absolute minimum of them is related to 2017 August 25 because of factors such as the transfer of liquidity from the futures market to the stock market at the election in Iran and the 12th of March (the absolute maximum point) because of reasons like managing investors towards secure assets due to fractures in the markets affected by fear of Trump have had dramatic changes in the aforementioned ratio.

Inflation expectations as one of the factors influencing inflation formation plays a decisive role in economic policy. Decision making and decision making in relation to issues such as consumption, savings, production, investment, the choice of asset portfolios, wages, exchange rates and interest rates are all shaped by inflationary expectations.In this study, the problem of formation of inflationary expectations among capital market participants in laboratory space using Z-tree software has been studied. To this end, Taylor's expanded rule first examined the central bank's behavior toward inflationary depreciation and estimated the Bank's central counterpart effect. The average inflation expectations of the participants in this experiment was 14.12%. Based on the results of this study, at a significant level, 95% of 34.7% of participants in this experiment formed their expectations based on the rational expectation pattern, 22.1% of individuals based on the matching pattern of expectations and 43.2% based on learning models. Therefore, monetary authorities, with the knowledge of how the formation of inflationary expectations among capital market participants can be appropriate policies, in line with the direction of existing liquidity towards the capital market, which controls inflation and prevents the movement of liquidity in the community towards the foreign exchange market and gold To adopt.