بررسی ساختار وابستگی و شبیه‌سازی عملکرد گندم دیم شهرستان میانه و متغیرهای آب‌ و هوایی: کاربرد رهیافت تابع مفصل تاکی‌شکل کانونی (C-Vine)

نوع مقاله: مقاله پژوهشی

نویسندگان

1 گروه اقتصاد کشاورزی، دانشکده کشاورزی، دانشگاه تبریز

2 دانشجوی کارشناسی ارشد اقتصادکشاورزی، دانشکده کشاورزی، دانشگاه تبریز

3 استاد اقتصادکشاورزی، دانشکده کشاورزی، دانشگاه تبریز

4 استادیار مؤسسه پژوهش‌های برنامه‌ریزی، اقتصادکشاورزی و توسعة روستایی

چکیده

بیمه آب و هوا از بهترین سیستم‌های بیمه‌ای است که در آن به منظور محاسبه حق بیمه، به شبیه‌سازی عملکرد محصول با توجه به متغیرهای آب و هوایی با تبیین ساختار وابستگی‌ آن‌ها نیاز است. بررسی ساختار وابستگی با در نظر گرفتن تأثیرگذاری هم‌زمان متغیرها با استفاده از توابع مفصل تاکی‌‌شکل می‌تواند نتایج مناسب‌تری ارائه کند. بنابراین، در پژوهش حاضر، ساختار وابستگی بین متغیرهای آب و هوایی و عملکرد گندم دیم با استفاده از توابع مفصل تاکی‌شکل کانونی (C-vine) اندازه‌گیری شد، سپس عملکرد گندم دیم در شهرستان میانه شبیه‌سازی گردید. نتایج مطالعه حاضر نشان داد که اکثر متغیرهای مورد بررسی دارای وابستگی دنباله‌ای در دم پایین‌اند؛ به عبارتی، تأثیرپذیری آن‌ها در مقادیر کوچک بیشتر از مقادیر بزرگ است. به این ترتیب، مقدار متوسط شبیه‌سازی شده عملکرد گندم دیم 6839/871 کیلوگرم در هکتار به‌دست آمد که این نتایج می‌تواند در محاسبه خسارت مورد انتظار و حق بیمه مورد استفاده قرار گیرد. 

کلیدواژه‌ها


عنوان مقاله [English]

Investigation of Dependence Structure and Simulation of Rainfed Wheat Yield and Weather Variables in Miyaneh County: Application of C-Vine Copula Approach

نویسندگان [English]

  • Esmaeil Pishbahar 1
  • S. Abedi 2
  • Gh. Dashti 3
  • A. Kianirad 4
1 Department of Agricultural Economics, Faculty of Agriculture, University of Tabriz
2 MSc Student of Agricultural Economics, Department of Agricultural Economics, Faculty of Agriculture, University of Tabriz, Tabriz, Iran
3 Professor of Agricultural Economics, Department of Agricultural Economics, Faculty of Agriculture, University of Tabriz, Tabriz, Iran
4 Assistant Professor and Scientific Board in Agricultural Planning, Economics and Rural Development Research Institute (APERDRI), Tehran, Iran.
چکیده [English]

Weather-based crop insurance is one of the best insurance systems in which it is required to simulate production yield with respect to weather variables and explaining of dependence structure to compute premium. The evaluation of dependence structure with consideration of simultaneous impact of variables using vine copula can provide more appropriate results. Therefore, in this study, the dependence structure between weather variables and rainfed wheat yield with utilization of canonical vine copula functions (C-vine) was measured and then yield of rainfed wheat in Miyaneh County has simulated. The result showed that most of the investigated variables have dependency in lower tail; in the other word, they are more impressible in small amounts than big amounts. Hence, the mean amount of simulated rainfed wheat yield was 871.6839 kg per hectare so that these results can be used in expected loss and premium calculation.

Weather-Based Crop Insurance, Simulation of Yield, Vine Copula Function, Rainfed Wheat, Miyaneh 

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