فصلنامه دانش مالی تحلیل اوراق بهادار
سال یازدهم شماره 39 (پاییز 1397)

The capital market in each country is considered as the most important part of the economy and its changes and fluctuation can reflect the full-fledged economic structure of each economy. The study of the global trend of convergence of stock markets indicates the interdependence of the economies of each other and the mobility of capital between countries. The stock market index reflects the trend of stock markets movements and it show the changes in the economy. In this study, the hypothesis of the convergence of the index of prices of stock markets in Middle East countries during the period from January 2007 to February 2017 has been investigated using cluster analysis method. The results show that the stock markets do not form a convergent cluster. However, there are two converging clusters between stock markets but the Jordanian stock market is not in any cluster and forms a non-convergent cluster

In recent years with the increasing integration and innovation in financial markets, concerns about the overall stability of the financial system has increased and the concept of systemic risk has become more important. systemic risk is the risk imposed by interlinkages and interdependencies in a system or market, where the failure of a single entity or cluster of entities can cause a crisis in the entire system or market. In this study, we presented a framework for measuring and predicting systemic risk in the capital market of Iran using conditional value at risk approach (CoVaR). On this basis, ΔCoVaR as a measure of systematic risk using quintile regression based on a set of state variables that indicates changes in the distribution of asset returns has been estimated. As well as to enhance the accuracy of the estimate, the research variables modeled after the conditional autoregressive value at risk model (CAViaR) has been developed and some Lagged firm specific characteristic has also been added. In order to test the validity of the model back testing methods have been used. On the other hand, The potential for systemic risk increases when volatility decreases (volatility paradox). In this study, we try to predict systemic risk by take advantage of the panel structure of the data and the relationship between ΔCoVaR and firm-specific variables that are available in certain sections

This study investigated the relationship between the comparability of financial statements with the expected crash risk stock prices in firms listed on the Tehran Stock Exchange. Information needed for the study of the financial statements of 117 firms in the period 1390-1394 has been collected. To test the hypothesis of multivariate regression with panel data is used. To calculate the variable comparability of the model De-Franco et al. (2011) and to calculate the variable crash risk expected stock price model Kothari et al (2009) is used. The findings of the research hypothesis and show that there is negative relationship between the comparability of financial statements with the expected crash risk stock prices. In other words, by increasing the comparability of uncertainty, incorrect analysis, investors and fear of further fall in prices will reduce the period of the crisis.

In this study, evidence is presented that shows the positive stock return-volatility relationship at the firm level is due to firm's real options. In the real options theory, it can be deduced:A) that the positive stock return-volatility at the firm level for those firms with more real options is much stronger and that the level of the sensitivity of the firm's stock return in response to the changes in the stock return volatility is significantly reduced due to the use of real options.
B) that, the relationship between return – volatility for companies that have fewer restrictions and greater capabilities to better respond to uncertain demands (greater flexibility) are much stronger. In the real options models, managerial flexibility leads to greater firm's value convexity function . Thus, according to the theory of Jensen's inequality, sensitivity of the firm's value due to volatility in firm's underlying assets, while increasing, it should help to strengthen the company's flexibility to the changes in investment decisions and operations

One of the concepts of management economics, which is a special application in the banking industry, is economies of scale. This concept refers to the change in production for the change in inputs and the benefits of lowering costs as a result of an increase in volumes of output. In this paper, Estimated economies of scale of 19 banks of the iran during the time period of 2011-16 was based on the commonly approach as well as the theory of constraints approach.The theory of constraints is one of the new theories of performance evaluation and is consistent with the cost leadership strategy with a systematic approach to the firm. Using the Translog model and Frontier4.1 software, the average economies of scale were estimated based on the intermediate approach of 1.35 (decreasing economies compared to scale) and, according to the theory of constraints, was 0.49 (increasing economies compared to scale). Paired-Samples T Test also showed a significant difference between the two approaches in SPSS software. This comparative study will be effective in increasing the managers' awareness of the effects of Throughput and creating a sustainable competitive advantage in the banking industry.

forecasting price movements is a challenging issue. So different statistical arbitrage strategies are devised to trade in exchanges. Some of these strategies are market neutral. Market neutral strategies are neutral to market movements and make profits in any situation. These strategies use long and short positions at the same time and this makes them unusable in exchanges like Tehran stock exchange that only long position is available. Purpose of this paper is devising a market neutral statistical arbitrage strategy which can be used in Tehran stock exchange. In devising this strategy we use principal component analysis to estimate market movements and calculate stocks idiosyncratic movements. To forecasting stocks idiosyncratic movements, which have mean reverting properties, we use Ornstein-uhlenbeck model. The strategy made 35% average annual return by considering transaction cost which is more than Tehran exchange index in the study period. results show this method is a good framework for devising statistical arbitrage strategies.

The inherent complexities of financial market contracts, including those made within the money and capital markets, and the effect of the financial market on the totality of the economic system of a country by providing financial resources motivate governments to use various instruments to secure finances and uphold public interests in these markets. The necessity to ensure the private interests of investors while minimizing and managing risks and the dual nature of regulation, which restricts market agents on one hand and constrains governmental intervention on the other, creates a vast continuum of regulatory instruments which are used in more or less all countries around the world in some manner. Regulation has transitioned through market crashes, government failures and the shortcomings of private law in attaining public and private interests, and has risen to the status of a government theory; it provides instruments and devices through which governments may select and deploy regulatory policies. In the present paper, Iran and the United Kingdom have been selected with respect to their differing points of departure on the regulation of financial markets and comparisons have been made regarding the strategies, methods, sanctions, resources and bodies which systematically facilitate one or many governmental policies which make up the regulatory mechanisms governing the financial markets in both countries.

The main objective of this study was to investigate the effect of oil price shock on stock returns in Tehran Stock Exchange ( TSE ) using Bayesian vector autoregressive model and seasonal time series data during the period of 1380-1394. Using the above model and considering the coefficients of the variables of the oil price growth rate, the effective rate of the real exchange and the gross domestic product, it can be seen that the effect of these variables on the stock market index is much higher than the rate of the concessional facilities rate. By comparing the action and reaction diagrams, it can be said that the shock of the oil market significantly reflects the fluctuations of the stock price index and, as time passes, shocks to the stock index will decrease. In fact, the shorter the period we take, the effect of the price shock on the stock price will increase.