Input and output technical efficiencies of wheat production in Kerman, Iran
利用1995年伊朗克尔曼省164个农场的Cobb-Douglas前沿生产函数数据，估计了产出导向和投入导向的技术效率指数，发现两者均受农场规模正向影响但解释力有限，表明通过增加产出或减少投入来提高盈利的空间有限。
The Iranian government encourages farmers to produce wheat (a common agricultural enterprise) by increasing farm productivity and efficiency.In this paper, using a Cobb-Douglas frontier production function, a simple relationship between a fatm-level output-based technical efficiency measure (the Timmer index) and an input-based measure (the Kopp index) is first developed.Then, using 1995 data from 164 farms in Kerman province, Iran, the average Timmer and Kopp indexes were estimated at 0.93 and 0.91, respectively, and were found to be similarly affected by farm size (positively up to about 9 ha) and by input ratios, though with rather small explanatory power.Thus, there seems some but limited scope to increase the profitability of Iranian wheat production either by increasing the product, given input levels, or by decreasing inputs for the current level of wheat production.However, since wheat producers may be able to adapt their production process more easily and quickly by implementing new techniques, i.e. by more efficient combination of inputs, than by adopting new technology, correction of input over-use can be regarded as a policy with speedy iflimited effect in this case.