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The present study evaluated the effects of reducing agricultural tariffs in different scenarios on food security and macroeconomic variables that using a computable general equilibrium model and data from Afghanistan's social accounting matrix. The effects of reducing tariffs were evaluated at 80%, 60%, 40%, 20%, and 100% (full liberalization). The results of this study showed that imports and consumption of cereals, fruits, vegetables, and livestock are gradually increased for households. Additionally, the increased purchasing power of households led to an increased demand for food, which improved food security and ultimately the health of households and society. Therefore, support for special facilities in the field of eliminating tariffs on agricultural products is essential.

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     One of the main inputs in manufacturing sector of Iran is fossil fuels with prices much lower than prices elsewhere in the world which are offered to producers and consumers. This accounts for a large share of subsidy payments allocated to different sectors of economy. The effect of subsidies on energy costs and prices of goods and services incur complex changes on the economy through allocation of resources. In this paper, using the computational general equilibrium model, effects of removal of fuel subsidies on production changes, cost and price in the Khorasan Razavi province has been studied. The results show that the elimination of subsidy on fossil fuels increased production, cost and price Indices. The highest growth rate of production and cost indices is in the gas sector and the highest growth rate of price index is in the oil sector.  

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Today, policymakers and economists use widely rational expectations (RE) in monetary, financial and regulatory policies to improve their country economic performance. In some of the pertinent models to these policies, expectations have been formed by assuming rationality and full information on economics. Indeed, economic agents have no perfect information about some parameters of these models. These unknown parameters can be estimated in the form rational expectations during learning process. In this research, the impact of government policies on the inflation rate has been modeled on the basis of rational expectations under learning process. Data has been gathered from Central Bank of Iran (CBI) and Iran’s economic development plans over the period 1989-2009. Results show that current inflation in the country originates mainly from economy structure and government policies, so share of public inflationary expectations is negligible. In addition, the learning process in Iran will converge to rational expectations, thus government policies for reducing inflation and increasing employment are inefficient. It is recommended that government adopt unanticipated and sudden policies to be effective its plans.

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In recent years, the high cost of raising livestock and, consequently, the sharp increase in the price of red meat in Iran have reduced its demand, and people consume chicken meat as a substitute for it. This has reduced the production incentives and, with the bankruptcy of some beef cattle farms, the welfare of producers and consumers of this product face serious danger. To overcome this problem, understanding cost structure and reducing consumer price by reducing production costs seems necessary. Therefore, the aim of this research was to evaluate cost structure and economies of scale of beef cattle farms in Mashhad. For this purpose, the short-run Translog cost function along with input cost share equations were estimated using the iterated seemingly unrelated regression method. The data were collected in 2017 from beef cattle producers by interview using structured questionnaires. The result showed that there were increasing returns to scale for all farms. In addition, the demands for all inputs were perfectly inelastic. On the other hand, there was weak complementary and substitute relationship between inputs. According to the results of this research, the most important factor of beef production in the selected farms was feed, whose demand was inelastic and the possibility of substituting it with other inputs was very weak. Therefore, the adoption of policies by the government, including subsidies for feeding cattle and increasing the import of this input, can reduce the production cost and prevent beef prices from rising.
 

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Planning for the agricultural sector requires identifying the limitations and capacities of field crops and horticultural production. Many studies in Iran have considered one or more dimensions of the agricultural sector; however, few studies have simultaneously examined the factors affecting the production of crops and horticultural products. For this study, data was gathered from 30 provinces in Iran during the period 2008-2016. First, PESTEL analysis variables were identified, and the I-Distance method was used to define the weight of each variable. Secondly, the PESTEL analysis dimensions were calculated by combining the variables of each index. Finally, the PESTEL analysis was combined with the econometric model of the spatial 3D panel. The resulting pattern was estimated by taking into account three dimensions, namely, time, province, and type of production (field and horticulture crops). The results showed that the indicator of environment is the most significant factor in the production of agricultural and horticultural products. Also, the investment factor and the supportive policies indicator are the most limiting factors in the production of field crops and horticultural products.

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Farmers’ trust in extension staff may improve the performance of agricultural extension services and productivity through transferred knowledge and new farming practices. Using the trust game and trust questionnaire, this study measured farmers’ trust in extension staff. Measures obtained from the two methods were statistically different. We examined the relationship between the measured trust and agricultural productivity to control socio-economic factors. The findings revealed an insignificant relationship between trust and productivity that might be due to inappropriate attributes of extension programs. This emphasizes the need for more participation of farmers in researching and structuring training programs. While age had a negative impact on trust, traditional farmers with high experience showed a high level of trust. This indicates that young farmers who mostly inherited their lands from their parents and have occupations other than farming or practice modern farming, do not trust the extension staff. Farm size positively influences productivity by reducing the number of laborers per hectare. This emphasizes that the traditional way of farming is the cause of low productivity in Iranian agriculture.