This paper suggests a composed option pricing model based on black-scholes and binomial tree models. So at first this two models are presented and analyzed. Then we showed black-scholes model is an appropriate option pricing model for stocks with low volatility and binomial trees model is an appropriate option pricing model for stocks with high volatility. Suggested model is a composed model of black-scholes and binomial tree models and volatility is used as selecting model factor. To determine volatility limit quantity, we calculated average volatility of Iran Stock Exchange. For this calculating we selected 32 stocks in two period of time. At the end of paper, suggested model is validated by 2 methods and it’s validity is approved by both of them.

Financial markets are currently experiencing sharp volatility. The turbulent environment of financial markets, the close relationship in these markets and the significant impact it has on the country's economy, as well as the urgent need to predict future financial and economic scenarios, have led researchers to explore and analyze these inter-market relationships. Studying how the returns and volatility in one market affect other markets has always been one issue that helps investors and policymakers to make optimal decisions. Given the importance of volatility spillovers in the Iranian financial market, this study aimed to investigate the effect of the volatility in the foreign exchange, gold markets to the capital market in Iran. In this regard, in this study, the effect of volatility spillover and noise trading of gold and foreign exchange markets on volatility in capital market returns has been investigated. This descriptive study was conducted using the daily and monthly data from the foreign exchange, gold, and capital markets from 2010 to 2019 and to analyze the data, ARCH and GARCH models have been used. The results of this study showed that the abnormal volatility of the capital market in the previous day positively affects the abnormal volatility of the capital market today, indicating that if money flows in the capital market, which indicates the flow of money in the capital market from yesterday, increasing the transfer of emotions to the current capital market. In addition, the abnormal volatility in the of gold and foreign exchange markets in the previous today has a positive effect on the abnormal volatility in the capital market today. The positive effect of this effect indicates the flow of money in the foreign exchange and gold markets and its volatility spillover into the capital market. Overall, the findings of this study confirmed the positive impact of the foreign exchange and gold markets on the abnormal volatility in the capital market in the short term (daily) and long term (monthly).

Volatility testShave for some decades been a major toolkit for economists in stock price analysis. While controversies and differences with market efficiency tests are better understood now than before, however the literature still has many examples where fundamental questions have yet to be answered. Here, we offer a starting point in dealing with fundamental issues for share prices in the Tehran Bourse not yet dealt with in previous studies.

In the last few decades, world financial markets have faced numerous volatilities and fluctuations. As a result active economic agents have become more interested in how to understand and foresee this fluctuation. Forecasting developments of the oil market has become ever more important after the oil crisis of the 1970s. The objective was to reduce the potential risk of such fluctuations by having advance knowledge of expected changes. Review of time series data of the West Texas Intermediate (WTI) prices indicate the presence of clustering volatility, can not be ignored in furcating. This has led us to focus in this study on the forecasting volatility of crud oil prices. We have used ARCH models to evaluate statistical errors of forecasts. The study results indicate continuous effect of shocks on conditional variance of crude oil prices. Future volatility of crude oil prices is dependent on oil price changes in the past. GARCH and TGARCH models perform better than other models of conditional variance in forecasting volatility of crude oil prices.

Firm investment is one of the important financial decisions in the economy, which affects the value of companies and the wealth of shareholders, which can result in increasing welfare. Despite neglecting the effects of uncertainty in traditional investment theories, modern theories have introduced various mechanisms for the impact of uncertainty on investment expenditures. Using the daily data of oil prices and the data of 131 companies listed on the Tehran Stock Exchange market during the period of 2008-2020, the factors affecting the investment of the companies are identified by emphasizing the oil price uncertainty. For this purpose, in the first step, the stochastic volatility model in the framework of the space-state approach is the basis for estimating the oil price uncertainty, and in the next, according to the results of the Hausman endogeneity test, the instrumental variable method is used to estimate the coefficients of the variables affecting investment. The findings indicate that first, the volatility of oil prices has no significant effect on investment. Second, firm size, profitability, inflation, and Tobin’s Q affect investment positively and significantly. Third, the financial leverage, which is reflected in the capital structure polices, has a significant negative effect on investment, meaning that more focus on debt financing leads to less corporate investment expenditures.