درخت حوزه‌های تخصصی

Khorasan Razavi Province suffers from the most critical groundwater resources in Iran, i.e. the groundwater decline has reached 1 m; 34 out of 37 water plains are banned in Khorasan Razavi Province. Recently, Mashhad plain has been fighting with the crisis of drought and water scarcity. Illegal harvesting from groundwater resources and the warming trend caused by change in climate have exacerbated the crisis. Comprehensive water resources management, assuming the complicated nature of water-related issues, rapid growth of population, water requirement for a variety of purposes, and limited water resources, requires novel methods to stack up technical, economic, environmental, social, and logical perspectives in an integrated forum. One of the tools for comprehensive water resources management is utilizing hydro-economic models to simulate the present status of drainage basins and evaluate the impacts of different scenarios and policies. The current study used a hydro-economic model to simulate the hydrological status of Mashhad plain and evaluate the impacts of different scenarios. Then, the agent-based model (ABM) was used in order to reach an agreement with stakeholders on executing different conservation scenarios. The hydro-economic model results revealed that reducing the water demand of the agricultural sector and, as a result, surface and groundwater consumption is possible through following adaptation scenarios. Implementing various adaptation scenarios may alter the present cultivation pattern. Moreover, the ABM results showed a significant difference between the volume of available water, due to the execution of strategies, and water demand, bringing about the lack of farmers’ cooperation regarding the implementation of conservation scenarios. However, through applying some incentive policies, a number of representative farmers may agree to pursue adaptation scenarios.

Risk and uncertainty are inherent characteristics of economic activities. This study aimed to investigate how fluctuations in macroeconomic variables affected the economic growth of Iran, in the period 1989-2021. To this end, fluctuations in macroeconomic variables were measured using EGARCH method, and then Iran’s economic growth equation was estimated based on the Markov Regime-Switching GARCH. The MRS(2)-AR(2) model was estimated. The model estimation results revealed two regimes of prosperity and recession in Iran's economy, the latter was more durable than the former in the studied period. The different effects of OPEC oil price fluctuations in the two regimes, indicating the asymmetric effects of this variable on Iran's economic growth. In other words, the effects of this uncertainty on Iran’s economic growth are smaller during a period of recession than a period of prosperity. The results on real exchange rate fluctuations showed that fluctuations in this variable had similar destructive effects on Iran’s economic growth. The results revealed the positive and negative effects of inflation rate fluctuations on Iran’s economic growth during periods of recession and prosperity, respectively. The IQI coefficient showed the positive effects of this variable on Iran’s economic growth; higher institutional quality increases physical capital and, thereby, economic growth. Based on the model estimation results, it is impossible to propose a single solution to control fluctuations in macroeconomic variables in Iran during different periods. economic policymakers should adopt and implement the best policies considering the periods of recession or prosperity as well as the development priorities.

The new structural economics approach to industrial policy is to follow a strategy of comparative advantage. According to this thinking, determining the relative prices of production factors by the market mechanism and providing the soft and hard infrastructure required by the government for industries that are compatible with the production factor’s structure, are the two determining factors of industrial development strategy. Considering that one of the key hypotheses of this approach is to increase economic growth as a result of comparative advantage following policy, this study has tried to test this hypothesis in the provinces of Iran in the period of 2005-2017 using the GMM. The findings of this study show that the hypothesis is confirmed at the level of Iranian provinces; Also, the change in the model estimation method did not change the research findings, so it is reliable. Therefore, it is recommended that policy makers consider the policy of following the comparative advantage of the region in designing the industrial development strategy.

Given the lack of a specific approach to the explanation of values of optimal portfolio weights in the portfolio optimization, the present study aimed to examine large-scale portfolio optimization according to both stock weighting and utilization of SCAD function to minimize the portfolio risk based on the "weight-modified conditional value at risk (CVaR)" and its comparison with the "conditional value at risk (CVaR)" method in the Tehran Stock Exchange. Therefore, the price information of companies listed in the Tehran Stock Exchange and Over-the-counter (OTC) from 2012 to the end of September 2020 was collected, screened, and analyzed daily, and then the risk and return of the portfolios were examined by forming optimal portfolios. The results indicated that the efficiency limit of the stock portfolio and also the ranks of different companies were different according to the types of the optimization method. Based on the behavior of the TEDPIX, the investors' degrees of risk-taking, and the risk management, diversification, and computational complexity of each method, the weight-modified CVaR had a better performance due to better diversification and risk management. Furthermore, the SCAD function added computational complexity to this method .

The oil market is affected by the supply of oil by oil-producing countries. The Organization of the Petroleum Exporting Countries (OPEC) was established in the 1960s to balance oil prices in favor of oil-producing countries. OPEC has gone through a period of convergence and divergence since its inception under political-economic events and crises. In turn, this convergence and divergence have had a significant impact on oil production, supply, and prices in the oil market. OPEC members form a diverse range of population, size, reserves, output, gross domestic product, ideology, and type of relationship with world powers. This diversity, along with internal tensions, leads to different approaches on energy markets and production quotas, which has affected the interests of all producing countries. Thus, this study aims to assess the convergence relationship between OPEC members on the strength of this organization on the market. To reach this aim, we have used a qualitative method of descriptive and analytical type using library resources and documents. Findings show that any lack of convergence and understanding between OPEC members has led to increased supply in the oil market and fluctuating prices. These price fluctuations seriously damage the economies of exporting countries.

Researchers examined anomalies in the market to understand the market dimensions. Prior studies considered the effects of biases on momentum strategy. Stock liquidity as one of the risk factors for assets was also considered by researchers. The purpose of this study is to examine the role of stock liquidity in the separately and jointly effect of anchoring bias and the disposition effect on momentum profit. The population of this study consists of all companies listed on the Tehran Stock Exchange. Based on systematic election sampling this study covers 136 companies over the period of 2007-2020. In this study, the effect of disposition effect is calculated using the approach of Greenblatt and Han (2005) and Frazzini (2006) and the anchorage bias is calculated according to George and Hwang (2004). This study calculates momentum profits according to Jegadeesh and Titman (1993). To test the hypotheses, multivariate regressions and the five-factor model of Fama and French (2015) have been used. The results of this study show that the disposition effect in stocks with low liquidity increases momentum profit. In addition, anchoring bias in stocks with low liquidity leads to an increase the momentum profit. Findings of this study document that the interaction effect of anchoring bias and disposition effect, while reinforcing each other, is also associated with increasing in momentum profit. Finally, when anchoring bias and disposition effect reinforce each other, and stocks have low liquidity, they do not increase momentum profits.