درخت حوزه‌های تخصصی

Simultaneous understanding of volatilities and changes in financial markets is very important to optimize the portfolio and risk management methods. The 2008 financial crisis led into devaluation of most assets, increased volatilities and endangered several institutional investors' survival. When the stock market' correlation is highly enhanced, risk and return management with the classic portfolio theory becomes severely challenging. In this study, to manage systematic and non-systematic risks by investors and policymakers in case of similar financial crises, the Effect of global financial crisis contagion is examined through the path of S&P500 global index, and DFM regional index of different industries of Iran Stock Market is examined using DFGM contagion test and stochastic Ornstein Uhlenbech process. The results show that Dubai Stock Market has an important role in crisis expansion into different sectors of Iran Stock Markets so that the fundamental contagion effects are channelled via this direction. Also, according to the results, the starting point of the global financial crisis contagion was the basic metals industry, and the contagin happened in metal ores and petroleum products sectors with different rates. Finally, the global financial crisis is spread into different industries of Iran Stock Market via financial links and not trough commercial ones. Identifying the direction of contagion of financial crisis provides an opportunity for investors to apply hedging and asset allocation strategies optimally.

The purpose of this paper is to investigate the role of managerial ability in information environment quality in the listed companies on the Tehran Stock Exchange (TSE). This research has focused on the quality of the information environment and has attempted to investigate the impact of management ability along with other variables affecting the information environment quality such as size, performance, accrual quality, etc. In this study, to measure the quality of a company's information environment "ratio of stock return volatility to market return volatility "  and to measure managerial ability The Demerjian et. al. (2012) model is used. The systematic elimination method was used for sampling 105 firms listed in Tehran Stock Exchange during the time range 2015 to 2021, and the model of panel data was applied to test hypotheses. Based on the research results while managerial ability can enhance the quality of a company's information environment, the size and growth rate of the company can also affect the information environment quality.