Estimation of Nutrient Elasticities: an Application of TOBIT Model

In this investigation, first the equation of food demand was estimated using an almost ideal demand system (AIDS) and Iranian cross sectional survey of income expenditure in 1384. Because of the cross sectional form of the data, the prices have calculated as marginal or unit values. Then with applying the elasticities of food categories, nutrient elasticities have extracted using Lancaster technology of consumption. These elasticities are useful to analysis the effects of aid policy on food demand and nutrient consumption respectively, and show the effects of the change in one food category price or food expenditure on the availability of each nutrient. In this article, as regard as demand equation is blocked-recursive simultaneous system, and zero value are existed as dependent variable, we use seemingly unrelated regressions (SUR) and tobit model.In another section, effects on demographic variables on food prices are examined. These variables are: age, education, region, urban or rural and Percapita income. Results have shown more food expenditure causes more food quality of food consumption and education, household size and other demographic variables are often effective on the quality of food.