مدل‌سازی بررسی عوامل مؤثر بر نوسان‏های قیمت محصولات کشاورزی ایران: مطالعه موردی خیار، گوجه‏ فرنگی، سیب‏زمینی و پیاز

نوع مقاله: مقاله پژوهشی

نویسندگان

1 استادیار گروه اقتصاد، دانشکده اقتصاد، دانشگاه شهید بهشتی، تهران

2 دانشیار گروه اقتصاد، دانشکده اقتصاد، دانشگاه شهید بهشتی، تهران

3 دانشجوی کارشناسی ارشد اقتصاد دانشگاه شهید بهشتی، تهران

چکیده

قیمت محصولات کشاورزی در مقایسه با سایر کالاها نوسان‌های بیشتر و شدیدتری دارد. آگاهی از ریشه‌های نوسان قیمت محصولات، سیاست‏گذاران را قادر می‌سازد تا سیاست‌گذاری‌های مناسبی برای کنترل این نوسانان‏ها و افزایش درآمد کشاورزان داشته باشند. بر همین اساس، دراین تحقیق عوامل مؤثر بر نوسانان‏های قیمت سبزی‌های منتخب (سیب‌زمینی، گوجه‌فرنگی، پیاز و خیار) در استان‌های عمده‌ تولیدکننده این محصولات بررسی شد. برای تعیین عوامل مؤثر بر نوسانان‏های قیمت از مدل‌های رگرسیونی با داده‌های تابلویی استفاده ‌شد. نتایج نشان داد ریشه‌های ایجاد ریسک در محصولات مورد مطالعه متفاوت است و ریشه‌های ریسک قیمت هر محصول را باید به‌صورت جداگانه بررسی کرد. البته افزایش نرخ سود تسهیلات بانکی بخش کشاورزی نوسانان‏های درون فصل قیمت هر چهار محصول را تشدید می‌کند. یک میلی‌متر انحراف از میانگین بارندگی در مورد خیار، گوجه‌فرنگی و سیب‌زمینی منجر به تشدید نوسان قیمت آنها می‌شود. انحراف یک درجه از میانگین بلندمدت دما در مورد محصولات خیار، گوجه‌فرنگی و پیاز موجب تشدید نوسان داخل فصل قیمت می‌شود. وجود قیمت تضمینی بالاتر از قیمت سرمزرعه منجر به کاهش نوسان درون فصل قیمت دو محصول سیب‌زمینی و پیاز می‌گردد. در پایان، پیشنهاد می‌شود نرخ سود تسهیلات بانکی بخش کشاورزی کاهش یابد و دولت در جهت افزایش قیمت تضمینی برای مؤثر واقع‌شدن آن در مورد محصولات فاسدشدنی اقدام کند.

کلیدواژه‌ها


عنوان مقاله [English]

Modeling the Fluctuations in Prices for Agricultural Products in Iran: A Case Study of Cucumber, Tomato, Potato and Onion

نویسندگان [English]

  • morteza tahami pour 1
  • A. Arabmazar 2
  • M. Hamedinasab 3
1 Assistant Professor, Department of Economics, Faculty of Economics, University of Shahid Beheshti, Tehran, Iran
2 Associate Professor, Department of Economics, Faculty of Economics, University of Shahid Beheshti, Tehran, Iran
3 MA Student in Economics, Faculty of Economics, University of Shahid Beheshti, Tehran, Iran.
چکیده [English]

In comparison to other commodities, prices of agricultural products have wider and more intense fluctuations. Knowing the origins of such fluctuations enables policy-makers to have appropriate policies for controlling them as well as it helps farmers to have a safe income. This study examined factors affecting the price fluctuations of chosen vegetables (potato, tomato, onion and cucumber) in major producing provinces of these products in Iran. For this purpose, the regression models with data panel were used. The results showed that origins of risks for the studied products were different and each product and its price had to be considered separately; in addition, for the four studied products, increased interest rates of bank facilities in the agricultural sector exacerbated the fluctuation of the season. A millimeter departure from the average rainfall would increase the price volatilities of cucumbers, potatoes and tomatoes and a degree of deviation of the long-term average temperature would exacerbate cucumber, tomatoes and onions volatilities in the price as well. The results indicated that guaranteed prices, though higher than farm prices, reduced the fluctuation in the season prices of potatoes and onions. So, the study suggested further emphasis on the policy of reduced interest rates of bank facilities in the agricultural sector; and the government should take action toward increasing the guaranteed prices to be particularly effective for perishable products.

کلیدواژه‌ها [English]

  • price
  • Price Fluctuation
  • agricultural sector
  • Iran
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