JOURNAL OF ECONOMIC MODELING RESEARCH
Year:2013 | Volume:3 | Issue:10|Papers Count:7

Informal economy i.e. unrecorded economy, is one of the important problems in developing countries which affects the efficiency of economic activities in formal sector. Informal economy is also an important source of air pollution. This paper aims at estimating informal economy in Iran over the period 1980-2009 based on the mount of CO2 emissions and the country forest areas and using Kalman Filter approach. The results indicate that: 1) there is a significant and long run relationship between CO2 emissions, the size of forest areas and firm’s industrial activities and total national product, 2) Total national product is more than recorded data in the study period so the existence of informal economy can’t be rejected during this period. 3) The average share of informal economy in total GDP is about 35.6%.

Storing the electrical energy in large scale is impossible. So, it is necessary to identify the factors affecting the electricity demand. Researchers have used different methods to forecast the future demand of electricity, among them intelligent methods and fuzzy based methods are more popular. Since ANFIS structure is based on researcher’s experience about phenomenon, the created structure may not have the best result. Therefore, we used PSO-ANFIS structure.In this paper long term electricity demand is forecasted until the year 2025 by hybrid PSO-ANFIS algorithm. The results confirm the high power of the Adaptive Neural based Fuzzy Inference System in forecasting the electricity demand. Results also indicate that the forecasted electricity demand will be 401 billion KWh in 2025. The prediction performance of the proposed technique is more accurate than the ARIMA model.

The estimation of output supply and inputs demand in farming sector with the assumption of full economic efficiency may result in false policy decisions. This article investigates the effects of irrigated wheat economic inefficiency on output supply and inputs demand in the period 2001-2009. After estimating the economic inefficiency by the use of production and cost stochastic models, the output supply and inputs demand of irrigated wheat are obtained through seemingly unrelated regression method. Results show that technical, allocative and economic inefficiency in irrigated wheat production in Iran are 21, 23 and 38 percent respectively. Moreover, the slope of output supply function is strongly affected by the related economic inefficiency in profit function and inefficiency changes input’s demand coefficients. Results also show that technical inefficiency has a greater effect on inputs demand compared to the allocative inefficiency.

The aim of this study is to calculate the marginal private and social costs of two thermal power plants in Isfahan region for a particular day in January 2010. For this purpose a nonlinear planning model with linear constraints has been used. The objective function (social cost) which is a twofold objective function is calculated by the summation of variable costs and external costs of power plants in the above mentioned region.The results of minimizing the objective function of private cost and also minimizing objective function of social cost indicate a significant difference between marginal social cost and marginal private cost. This difference is considered as marginal external cost in peak hours of electricity consumption and has had an obvious increase to the off-peak hours of electricity consumption in the region of the study. Taking into account the social costs of electricity generation, green power generation technologies can compete with thermal power plants.

Today the quantitative assessment of economic and social impacts of petroleum products supply constraints is one of the main policy issues in Iran. This issue arises from the fact that importing gasoline, gasoil and liquefied petroleum gas (LPG) is restricted by international sanctions. In this paper, we showed that a demand driven Social Accounting Matrix (SAM) is not a suitable tool for answering the above question. So, a modified SAM, known as mixed supply driven SAM is suggested. For this purpose the energy SAM of 2006 is used.The overall results reveal that: 1) Petroleum products supply constraints have the most impacts on crude oil and natural gas, retail and wholesale, chemical and agricultural sectors. 2) Operating surplus has the most reduction among the other production factors. Results also showed that the fall of urban income as a consequence of supply constraints is more than rural labor either relatively or absolutely.

Oil revenues play a significant role in the government budget in Iran and have also an important impact on GDP. This study aims at providing a practical solution for the question of how oil revenues should be managed. In this regard, a Computable General Equilibrium (CGE) model has developed to examine the direct effect of distribution of oil revenues on GDP in both static and dynamic approaches.The results of static model show that the direct distribution of oil revenues to households has a negative effect on the government expenditures and therefore decrease the GDP. The dynamic model allows the conversion of savings into investment and capital formation. So the results of running this model show the positive effect of direct distribution of oil revenues on GDP and also the negative effect of this policy on the government current spending. Therefore, the results confirm that direct distribution of oil revenues is an effective policy in reducing the dependence of government on oil revenues and also in relying more on people and the tax revenues.

In this paper we revisited the recent study examines the determinants of Intra-Industry Trade (IIT) in the agriculture, industry and services sectors between Iran and European Union, ECO, GCC and ASEAN countries in the period 1980-2009, using a dynamic panel data.This study uses country-specific characteristics as explanatory variables. The results indicate that IIT is a negative function of the difference in GDP per capita between Iran and trade partners. There is also a statistically significant relationship between IIT and the countries demand similarities. Results also reveal the importance of the size of economy and product diversification in intra industry trades. Finally the hypothesis that trade increases by a decrease in transportation costs can’t be rejected.