Homayoun Ranjbar - Faculty of Humanities and Law, Department of Economics, Islamic Azad University of Isfahan (Khorasgan) Branch, Isfahan, Iran.
Helen Mozafari Shamsi - Faculty of Economics, Management and Social Sciences, Shiraz University, Shiraz, Iran.
Vahid Mohamadi - Tehran Faculty Petroleum, Petroleum University of Technology, Tehran, Iran.
Fatemeh Mirzaii - Department of Economics, Islamic Azad University of Isfahan (Khorasgan) Branch, Isfahan, Iran.

Investigating the import demand function has particular importance in identifying the macroeconomic models and effectiveness and commercial efficiencies of the Iranian economy. For this reason, one of the major issues that can be addressed in the field of importing goods is the estimation of import demand function and investigation of impacting factors on imports. Therefore, in this paper, by using seasonal data for the period ۱۹۹۲-۲۰۱۷ and applying the almost ideal demand system (AIDS), and using a seemingly unrelated regression (SUR) econometric technique, we have estimated import price and income elasticities for five commodity groups based on one-digit tariffs code for the Iranian economy. The empirical results indicated that the import allocation pattern is single-stage and depends on domestic sales. In addition, the own-price elasticities had a negative sign that supports import behavior. Cross-price elasticities also showed a poor complementarity between the other portable and metal commodities and, Social & personal services and Financial & Business Services, domestic sales with Agricultural, forestry & fishing products, other portable & metal commodities, and Financial & Business Services groups. The expenditure elasticities in five commodity groups were significant, except in the first group, which implied the effectiveness of demand for each commodity group relative to income.

almost ideal demand system, Elasticity of Demand, Import Allocation Pattern, Seemingly unrelated regression