آيا واردات برنج به ايران بي رويه است؟

Is Rice Import Unjustified in Iran

استمرار واردات برنج به كشور همزمان با افزايش توليد داخلي اين محصول، فرضيه بي رويه بودن واردات اين كالا را در ميان توليدكنندگان داخلي آن شكل داده است. مطالعه حاضر در پي آن است تا اين فرضيه را مورد ارزيابي قرار دهد. براي اين منظور ابتدا با بهره گيري از رويكرد تجزيه و تحليل اكتشافي اطلاعات (EDA) ارتباط بين واردات و توليد داخلي و همچنين ساير عواملي كه از جنبه نظري مي توانند واردات اين كالا را در دوره 93-1360توضيح دهند، ارزيابي گرديده است. سپس، ارتباط بين واردات و اين عوامل با استفاده از روش هاي اقتصادسنجي كمي شده است. نتايج حاصل از تجزيه و تحليل اكتشافي اطلاعات نشان مي دهد تنها دو عامل درآمدهاي نفتي و رشد جمعيت ارتباط قابل توجهي با واردات برنج دارند. اين نتيجه در كنار اين واقعيت كه تجزيه و تحليل اكتشافي اطلاعات بيانگر روند كاهشي قيمت واقعي برنج در دوره مطالعه است منجر به اين نتيجه گيري مي شود كه فرضيه بي رويه بودن واردات برنج درست است. نتيجه حاصل از تجزيه و تحليل اكتشافي اطلاعات توسط روش هاي همگرايي و الگوي اقتصادسنجي ECM نيز تاييد مي شود. با توجه به اين نتايج، جدا سازي ميزان واردات برنج از درآمدهاي نفتي و محدود كردن واردات با در نظر گرفتن كشش تقاضا براي اين كالا بگونه اي كه همواره قيمت دريافتي توليدكنندگان از روند رشد تورم در كشور پيروي نمايد پيشنهاد مي شود.

Introduction: The persistence of rice imports while domestic production shows an increase over time has resulted in forming this hypothesis among rice producers in Iran that import of the rice is unjustified. This study is seeking to evaluate this hypothesis. Materials and Methods: The relationship between the import of rice and the quantities of domestic production as well as the other theoretically possible factors explaining import over period 1981-2014، including domestic/world market relative price، exchange rate، domestic income، population، tariff rate are investigated using exploratory data analysis (EDA) approach. In addition، the relationship between import and these factors is quantified using ECM econometric methodology. Furthermore، the VAR framework is utilized to specify causality between the above-mentioned variables and quantities of rice imported. Results and Discussion: Results from EDA revealed that there is not a clear relationship between the quantities of domestically produced rice and the imported quantities، while such a relationship is shown between per capita crude oil revenue and the quantities of rice imported. In addition، the quantities of imported rice are not related to the domestic/world price ratio. Moreover، EDA shows a decreasing trend in real domestic price of rice. Results from EDA are supported by the co-integration and ECM methodology. The Granger causality between per capita crude oil revenue and the quantities of rice imported which was tested within VAR framework indicates that there is a one way causality from the first variable to the second one. Furthermore، the estimated ECM shows that the effect of per capita crude oil revenue on quantities of imported rice is higher in log relative to the short run. A one-dollar increase in per capita crude oil revenue results in 360 metric tons import of rice in the long run while the same one dollar increase will result in 290 metric tons import of rice in the short run. These results support the hypothesis that import of the rice is an unstructured import which may hurt domestic rice producers. Finally، calculation of the intra industry trade index indicates that intra-industry trade theory cannot explain the increasing trend of rice import in Iran. Conclusions: Given that the per capita oil revenue is the main determinant of the rice imports، besides the fact that EDA shows a decreasing trend in real domestic price (terms of trade) of rice and reaching below one led to the conclusion that the unjustified import hypothesis is confirmed in Iran. Accordingly، a revise in rice import is suggested. Specifically، decoupling rice import from crude oil revenues and limiting import، using price elasticity information، to keep an increase in the price of this commodity equivalent to the CPI growth rate for domestic producers is suggested.