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Estimates of technical inefficiency in agricultural production are suspect so long as variations exist in production technology among the sampled farmers. Traditional methods of dealing with these technological differences risk attributing "technology gaps" to technical inefficiency between farms, pointing to the need to undertake a metafrontier analysis that allows technology gaps to be distinguished from technical inefficiency. Using farm-level data on the production of three different varieties of pistachio trees in Iran, we outline two criteria to justify its use: an inability in farmers to switch between production technologies except in the long term, and satisfaction of statistical tests on metafrontier coefficients. The application of metafrontier analysis enabled technical efficiency scores to be corrected for differences in production capacity imposed by tree variety. Results reveal that there is very little difference in technical efficiency between farms growing the different tree varieties. But they show that ignoring the production constraints imposed by variety choice could overstate the scope for farmers to improve their technical performance by adopting better farming practices. The results also indicate that it is misleading to compare the performance of different tree varieties on the basis of yield per hectare alone.

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The exchange rate overshooting, which results from the monetary disruptions, has negative impact on production and investment in the main economic activities and de-stabilizes the whole economy because of their input-output linkages. Therefore, identifying the causes of economic instability can help to adopt appropriate policies and to create economic stability in the country. The main question is to what extent the exchange rate can cause instability in the economy. To answer this question, first, the exchange rate overshooting was calculated using the Hodrick- Prescott filtering method during 1989-2012. Then, it was introduced into the model by specifying the generalized Solow production function, and finally, the production function was estimated for the main activities of the economy using the panel data technique. The results show that the impact of the exchange rate overshooting on the major economic activities is negative.

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Population growth and loss of environmental capacities for food production have rendered the realization of food security a more complicated task as compared to the previous decades. To cope with this crisis, sustainable agricultural development can play a remarkable role in improving food security. The present study aimed to explore the spatial effects of agricultural sustainability on food security of rural households in 30 provinces of Iran over the period of 2006-2016. For this purpose, first, the overall level of agricultural sustainability using a Composite Sustainable Agriculture Index (I_CSA) and weighting indicators were calculated based on Analytic Hierarchy Process (AHP) method. The Aggregate Household Food Security Index (AHFSI) was used to determine the food security of households in rural areas. Also, the effectiveness of agricultural sustainability on food security of rural families, as well as other effective factors, was examined using the mixed Spatial Autoregressive (SAR) model with panel data. Results show that the spatial spillovers of the agricultural sustainability influence food security positively and significantly. In fact, 1% increase in the agricultural sustainability index of a certain province directly improves food security of the same province by 0.043%, while its food security is indirectly enhanced by 0.0131% with 1% increase in the agricultural sustainability index of other provinces. It is imperative for policymakers of the agricultural sector to invest in production infrastructure of different provinces in Iran and focus on enhancing sustainable production as a prerequisite for the establishment of sustainable food security.