بررسي تقاضاي شير و انواع تخم پرندگان در مناطق شهري ايران

Demand for Milk and Various Types of Bird-Eggs in Urban Iran

This study gives estimates of demand functions for milk and various types of bird-eggs in urban society, using Almost Ideal Demand System (AIDS), and examines price and non-price elasticities of compensated and non-compensated demand functions. As indicated by the produced results, over the studied period (1979-2002), budget ratio allocated to the various types of bird-eggs was higher than that allocated to the milk, though the latter was gradually increasing during the latest years of the period, which might be due to the advertising of milk consumption. Self-price elasticity of the various bird-egg types in the urban society suggest that the application of price instrument to improve consumption pattern has not been effective over the studied period. It indicates that it is of a particular importance to include variables like growth in productive activities and growth rate of population in optimal management of demand. These variables should be directed to optimisation by applying suitable policies. However, given the necessity to provide urban households with both of these consumption goods, and considering decreased real expenditures (incomes) of the households due to severe increase in price indexes, it would not be a suitable policy to remove subsidies paid for such goods; rather, there must be a policy to decrease subsidies gradually, parallel to the control of inflation. Moreover, because of using time series data, first, the unit root in variables of the concerned model and then, longterm relation of the data are reviewed. Results of the study indicate that there are a uniform convergence and a long-term relation among the variables of the model.