انتخاب تابع توليد براي برآورد ارزش اقتصادي آب كشاورزي مطالعه موردي توليد گندم

Choosing an empirical production function to estimate economic value of irrigation water : A case study of wheat production

In this study, the effect of the choice of production function on the estimated structural parameters, and also the importance of correct functional form specification to prevent incorrect policy implications are shown. To this end, first, a number of flexible and inflexible functional forms which are assumed to represent the wheat production process in Alavian region are estimated. Then, the economic values ofʹ water are computed based on the estimated parameters of various production functions. A comparison of economic value of water input derived from parameters of the correctly specified functional form, using the econometric criteria and specification tests, with those of the inappropriate functional forms. reveals a substantial difference between the computed values for the water input. This leads to conclusion that the cost of functional form misspecification can be considerable if such information is used as a basis for a new policy formation in the agricultural sector.