فصلنامه مدلسازی اقتصادی
سال هشتم شماره 1 (پیاپی 25، بهار 1393)

Financial crisis، especially after 2007-2010، has been considered as one of main concerns of financial economists. They are worried about its continuation leads to a prolong recession in global economy. Thus، this paper is targeted to test the feasibility of the resistance of Islamic finance and banking when confronting crisis in question. By using analytic- descriptive method، it is to evaluate whether Islamic finance simmers down the crisis. As a result، it is clear that theoretically speaking Islamic finance does have sufficient capability to prevent crisis. Its effectiveness، however، depends on actual performance of economic agents to pay attention to requirements of applying those teachings in actual life and not in mere proclamation.

Transportation is one of the most polluting divisions of economical interest، though it has various important negative effects on the national economy. Thus، environmental considerations in this field should be accounted for by high priority. In this work، by using different pollution parameters in transportation، consumption and production divisions، the effects of shadow price of environmental pollutants resulting from combustion of fuels on value added growth will be investigated through structural time series model (STSM). Since، shadow price of the environmental pollutant must be extracted initially; the instantaneous frontier pattern is used. Hence، after the evaluation of shadow prices in the transportation field، total prices for CO2، NOx and SO2 are calculated by assuming the individual diffusion contributions from those of the total contributions. Finally، the effects of these totally calculated results on value added growth are investigated by considering other defining variables. The resulting coefficient of shadow price growth by the value of -0. 25 indicates inverse relation for this price between the transportation and value added growth.

This study tries to examine the impact of liberalization on the price of energy carriers including gasoline، kerosene، gasoline، fuel oil، LPG، electricity and natural gas on agricultural sector in Iran by using Social Accounting Matrix. Despite of 13-20 percent of agriculture contribution to GDP and employment، only 3. 8 percent of total energy consumption is allocated to it during 2001-2009. The results of Social Accounting Matrix represent 57 and 41 percent growth in producer price index of agricultural products according to two scenarios (the average growth percentage of 2100 and 1570 in energy prices). Gasoline، by 40 percent of total direct and indirect effects، has the highest share in the increase of price index of agricultural production. To compensate the energy price liberalization on the agricultural sector، prolonging the rise of energy prices in the agricultural sector، preferential prices for electricity use in agriculture and energy efficiency in agriculture can be proposed.

This paper reveals how many percent of Iranian households consume 100 percent of their current income or apply rule-of-thumb in consumption. To get the goal، Epstein-Zin utility function thereby will separate the elasticity of inter-temporal substitution and relative risk aversion. Then، the coefficient of rule-of-thumb in consumption will be estimated during 1980-2012 by using Generalized Method of Moments (GMM). Results indicate that about 26. 5 percent of the Iranian households represent rule-of-thumb behavior، but the restact based on PIH and have inter-temporal consumption plan. Also، the coefficient of risk aversion for the consumption of Iranian households is about 8-22 percent.

The purpose of this paper is to extract the components of long-term business cycle trend and irregular impulses of real GDP، and also considering the status of agriculture in Iran business cycle. Real GDP is segregated by using Hodrick–Prescott filter and cyclical feature of key variables influencing the business cycle will be analyzed and calculated. Then، by the use of VAR model and response function، the measure of business cycles shock is considered. The results of the business cycle represent that Iran economy has experienced five complete business rounds during 1971-1980. The results show agriculture has a positive and statistically significant impact on GDP gap in long-term. Also، the results of the cross-correlation coefficient indicate that agriculture sector has been a backward variable toward GDP gap during the years 1971-1980 and 1981-1989، but it has been a leading variable during 1990-2008. This indicates that agriculture sector is considered as a driving factor in business cycle during the third period.

Social security، as one of the largest insurance agencies covering 37 million people of the country population and 63 thousands employees by vast areas of insurance، medical and investment services، has vital effect on the social and economic structure of the country. Consequently، the evaluation of this organization is of high significance. Moreover، DEA is a non-parametric method by solving linear programming problems for evaluating the performance of decision making units by multiple inputs and multiple outputs. In this paper، the efficiency of social security branches in Isfahan Province will be evaluated by DEA during 2011. In continue، efficient and inefficient units of this branch are identified and then efficient units will be ranked by Anderson and Peterson Model.

Natural gas high consumption in home sector is an important issue in Iranian economy. The data confirm that the increase of natural gas consumption in Iran is dramatically high near 9. 9 percent. This paper estimates long run and short run natural gas demand by using ARDL، ECM models during 1999-2009. The results indicate that natural gas can''t be substituted by electricity; there is a long run relationship between the variables; price elasticity of natural gas is -0. 12 and -o. 36 in short run and long run respectively but not statistically significant and income elasticity، in short run and long run، is 0. 627 and 0. 88 respectively.