Journal of Economic Modeling Research

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Industrial energy demand analysis has always been one of the leading fields of research in economics. This issue is more critical in the case of developing countries especially those with transition experiences. In this paper, third generation of dynamic factor demand models for the Iranian manufacturing industries is estimated to analyze the speed of adjustment in factor demands. Data which is used in this study is an Iranian industrial plant based on two-digit international classification code during 1374-1386. The translog functional form is used as model specification. The main findings are the complementary relation between energy carriers, electricity, and capital and low adjustment speed of capital stock. In Iranian manufacturing industries, demand for energy carriers and capital, with expansion of manufacturing activities and technological change has increased, while the demand for labor has decreased.

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Public pricing of products is one of the most important economicalissues, since any changes in the pricing, affects both the welfare ofconsumers and quantity of goods and Services which are produced.
In this paper which is done for natural gas pricing  in Iran, the purpose is giving a price that the government can consider it as a suitable choice for using in subsidies targeting project. These prices have two advantages: first, they try to maximum the social economical welfare (summation of producer and consumer surplus) second, this method solve the problem that the producer has in covering their costs (by marginal cost pricing) because of increasing returns to scale.
This paper deals with the optimal gas pricing in household sector in Iran by the Ramsey method of pricing.
In this regard we have used fuzzy regression (because of its accuracy and devoid of classic regression restrictions) and the data from 1977 to 2011 for estimating production function and returns to scale in natural gas production side. Also for estimating demand function and elasticity we have used ARDL method and data from 1350 to 1389. The results shows that the current prices aren’t optimum and despite implementation of subsidies targeting project the prices are low.

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In recent decade in developing countries, lack of government budget or lack of access to modern technology, persuade governments to attract private sector participation in the economy. One of the most common methods is Public-Private Partnership agreements. The real implementation of this type of partnership needs to set contracts that satisfies preferences of both parties. This research aims to solve this problem using the solutions available in the Contracts Therory Knowledge. Theoretical modeling with analyzing public-private partnership model, provide an optimal model for BOT contract. We use library method to explain the basic contract and mathematical modeling  by MATLAB software with Particle Swarm Optimization to specify the parameters of utility functions and to provide optimal contract. 
The simulation results for an optimal contract were calculated using the supposed parameters (life time, incom, costs, future incoms discount rate, salvage value of project costs) 38 years (project utilization time), 78% (principal participation after transfer time), 45% (principal participation during the operation), 7% (riskes to the principal).