استفاده از مدل ناپارامتریک تصادفی فراگیر داده‌ها (StoNED) برای محاسبه کارایی انرژی تولید گندم در استان مازندران

In current research, energy efficiency and technical efficiency of wheat farmers were calculated in Mazandaran province. To estimate technical efficiency the Stochastic Nonparametric Envelopment of Data (StoNED) was used. The model incorporating nonparametric data envelopment analysis model which contain the smoothness and concavity constraints with stochastic frontier analysis model. The requirement data for this study was include 375 farmers in 2012. The results showed that in production of wheat, nitrogen, seed and fuel with 41.7, 25.4 and 20.5 percent have the largest proportion of input energy and manpower with 0.21 percent and herbicides with 0.53 percent have the lowest percentage of energy. A total of 15761.5 MJ of energy input and 62.8 MJ output energy in wheat production systems was calculated. About 20.7% of the input energy in wheat production systems was direct energy and 79.2% of its energy was indirect form. Renewable energy sources is about 25/6% of the total input energy and non-renewable energy sources is about 74.3%. Energy productivity is 0/29 MJ/ kg and means that each unit of energy can produce just 0/29 kg of product. Average energy efficiency per hectare obtained 3/99 for wheat. The net and specific energy were 47066.9 MJ/ha and 3.4 MJ/Kg respectively. The average technical efficiency, pure technical efficiency and scale efficiency was 0.46, 0.45 and 0.43, respectively. About 46.4% of the farms have constant returns to scale, 24.8% of the farms have diminishing returns to scale, and 28/8 percent is increasing returns to scale.