Assessing the Efficiency of the Value-at-Risk Index (VAR) using Extreme Value Theory in comparison with traditional risk assessment methods

Generally, the greatest risk in the capital market or in the portfolio of investors occurs when large sudden changes occur in the unfavorable portfolio. These losses are in the distribution sequence, and for this purpose they are called "limitative values". In this research, the logarithmic efficiency of the Tehran Stock Exchange Index based on the information received during the time interval between the day (due to the use of high frequency data) during the years 1392 to 1395, and the use of the maximum block approach in measuring the VaR value index is used. It turned out VaR index was calculated using historical simulation methods and variance-covariance method as the traditional risk assessment criteria and the results were compared. The results of data analysis in R software showed that the use of monthly information in calculating the risk-weighted value index has a higher predictive accuracy and the error rate (test error) in this case is lower than traditional risk assessment methods.