Petroleum Business Review

Abstract This study uses spatial econometric and dynamic analyses to examine the temporal and spatial effects on three performance indicators of petrochemical companies active in the Tehran Stock Exchange: price performance, retained earnings, and total performance. The target population comprises all petrochemical companies listed on the Tehran Stock Exchange that have been active since the beginning of 2013 to the end of 2024. The findings suggest that, while information asymmetry positively influences companies' retained earnings, it simultaneously has a negative impact on price and total performance. Additionally, an examination of the H-index revealed that the market structure of this industry is monopolistic. However, monopolistic behavior is observed in the distribution of retained earnings, which can be attributed to the centralized structure governing the management of the Iranian petrochemical industry. Findings concerning financial structure suggest that elevated financial leverage and financing costs negatively impact returns, while investment in physical assets has the most favorable impact. Furthermore, identifying significant spatial effects corroborates the idea that proximity and spillover effects between companies are substantial. This study provides substantial empirical evidence that enhancing information transparency, optimizing financial structures, and reforming corporate governance mechanisms could increase market returns and improve stock returns in the petrochemical industry.

Abstract Market uncertainty is when investors have difficulty in assessing current and future market conditions because there is a lot of volatility in the market. This research was conducted with the aim of investigating the effect of environmental uncertainty and currency uncertainty on volatility of stock returns of Petrochemical and Petroleum Products Supplier companies which are listed in Tehran Stock Exchange (TSE); these companies are active in all areas of the supply chain from extraction to retailing. In order to achieve the objectives of the research, research hypotheses were tested based on a statistical sample consisting of 13 companies during a 10-year period from 2012 to 2021 through the GMM estimation method with EViews. The findings of the research show that environmental and currency uncertainties intensify the volatility of companies' stock returns. These uncertainties in the previous period have the opposite effect on the volatility of stock returns in the current period. Also, the relationship of trading volume and stock price variables with stock return volatility is negative, because when market uncertainty is high, traders are expected to move more towards stocks of safer companies. The greater the volatility of returns in the previous period, it is expected that this will intensify the volatility of stock returns in this period as well. Examining volatility of stock returns can be useful in analyzing market participants' motivations.