بررسی ساختار هزینه فرایند عرضه آب (مطالعه‌ موردی شرکت آب و فاضلاب شیراز)

نوع مقاله: مقاله پژوهشی

نویسندگان

1 استادیار بخش اقتصاد، دانشگاه شیراز

2 دانشجوی دکترای علوم اقتصادی، دانشگاه شیراز

چکیده

هدف اصلی این مقاله بررسی شاخصهای بازدهی نسبت به مقیاس و صرفه‌های ناشی از مقیاس که دلیلی بر وجود انحصار طبیعی است و همچنین بررسی وضعیت تغییرات تکنولوژیکی و نرخ رشد بهره‌وری عوامل تولید در شرکت آب و فاضلاب شیراز بود. به این منظور از فرم تابع هزینه ترانس‌لاگ برای برآورد تابع هزینه فرایند عرضه آب در این شرکت استفاده شد. چارچوب تجزیه و تحلیل بر مبنای روش رگرسیون‌های به‌ظاهر نامرتبط تکراری بود. برای براورد پارامترهای تابع هزینه از داده‌های سری زمانی فصلی طی دوره زمانی 1378 تا 1385 استفاده شد. در این شرکت از چهار عامل تولید: نیروی کار، سرمایه، مواد اولیه و سایر خدمات در فرایند تولید بهره گرفته شد. نتایج حاصل از تحقیق حاکی از وجود بازدهی کاهنده نسبت به مقیاس و عدم صرفه‌جویی ناشی از مقیاس بود که وجود انحصار طبیعی در این شرکت را رد می‌نمود. شاخص پیشرفت تکنولوژی حاکی از کاهش هزینه‌ها در نتیجه پیشرفت تکنولوژی و محاسبه شاخص رشد بهره‌وری نیز نشان دهنده وجود رشد بهره‌وری در طول دوره مورد مطالعه بود.

کلیدواژه‌ها


عنوان مقاله [English]

An Analysis of Cost Structure Process of Water Supply(The Case Study of Shiraz Water and Wastewater Company)

نویسندگان [English]

  • Hossein Marzban1 1
  • Leila Karimi 2
1 Assist. Prof. of Economy, Shiraz University
2 Ph.D. Student of Economic Sciences, Shiraz University, Shiraz
چکیده [English]

The main purpose of this paper is examination of return to scale index and economics of scale index that is an argument of being natural monopoly, also investigation on states of technical changes and productivity growth rate in Shiraz water and wastewater company. This is the reason translog cost function is used to estimate the cost function of the water supply in this company. The framework of analysis is in accordance to the iterative seemingly unrelated regression (ISUR) technique. To estimate the parameters of the cost function we have used the quarterly data for the period of 1999-2006 has been used. This company uses four factors of production in its process: labor, capital, raw material and other services. The result showed that there exists decreasing return to scale and no economizing of scale that rejects the existence of natural monopoly in this company. Advance technology index indicated cost decrease as a result of advance in technology and calculation index of productivity growth showed the existence of productivity growth during the surveyed period of time.  

کلیدواژه‌ها [English]

  • Natural Monopoly
  • water supply
  • translog cost function
  • Return to Scale
  • Sequential Iterative Seemingly Unrelated Regressions
  • Water and wastewater
  • Shiraz
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