کاربرد تابع‌های مفصل در تعیین حق بیمۀ مبتنی بر شاخص تنش گرمایی گاوهای شیری (بررسی: شهرستان دماوند)

نوع مقاله : مقاله پژوهشی

نویسندگان

1 استادیار بخش کشاورزی، دانشگاه پیام نور، تهران، ایران

2 دانشجوی دکتری اقتصاد کشاورزی، پردیس بین الملل دانشگاه فردوسی مشهد

چکیده

طراحی و اجرای بیمۀ آب و هوایی شاخص دما-رطوبت یک ابزار مناسب مدیریت خطرپذیری است که می‌تواند آسیب و زیان دامداران را در برابر تنش گرمایی کاهش داده و به تثبیت درآمد آن‌ها منجر شود. با توجه به این مهم در این پژوهش، این نظام بیمه‌ای برای فعالیت پرورش گاو شیری در شهرستان دماوند طراحی شده است. داده‌های مورد نیاز به‌صورت ماهانه و از مدیریت جهاد کشاورزی و ایستگاه هواشناسی شهرستان دماوند برای دورۀ 95-1391 گردآوری شد. به دلیل انعطاف‌پذیری رهیافت مفصل و دقت بالا در اندازه‌گیری ساختار وابستگی، از این روش برای تبیین تابع توزیع همزمان و اندازه‌گیری آسیب مورد انتظار استفاده شد. نتایج نشان داد، بین عملکرد گاو شیری (شیر) و شاخص دما-رطوبت همبستگی منفی قوی وجود دارد که توسط مفصل کلایتون چرخشی منفی بهتر از دیگر مفصل‌های تبیین می‌شود. حق بیمۀ شاخص هوایی برای گاو شیری 65/610 هزار ریال در سطح پوشش 100 درصد محاسبه شد. همچنین آسیب مورد انتظار ناشی از تنش گرمایی در سطح پوشش 100 درصد برابر 42 کیلوگرم در ماه برای هر رأس گاو شیری به دست آمد که با توجه به شمار کل گاوهای شیری در شهرستان (2207 رأس) آسیب و زیان کل ناشی از تنش گرمایی برابر با 92694 کیلوگرم در ماه و رقمی بالغ بر 2/1 میلیارد ریال در ماه محاسبه شد. با توجه به بزرگ بودن آسیب و زیان ناشی از تنش گرمایی و اهمیت شیر در سلامت جامعه، توصیه می‌شود مسئولان و سیاست‌گذاران به طراحی این نظام بیمه‌ای در کل کشور توجه خاص و ویژه کنند.

کلیدواژه‌ها


عنوان مقاله [English]

The application of copulas approach in determining heat stress based index insurance premium for dairy cows in Damavand county

نویسندگان [English]

  • Afsaneh Nikoukar 1
  • Sasan Torabi 2
1 Assistant Professor, Department of Agriculture, Payame Noor University, Tehran, Iran
2 Ph.D. Student of Agricultural Economics, International Campus of Ferdowsi University of Mashhad, Mashhad, Iran
چکیده [English]

Designing and implementing temperature-humidity index insurance is a proper risk management tool that can lower animal breeder loss against heat stress and can lead to their income stability. Given this important issue in the present study, this insurance system has been designed for dairy cattle production in Damavand County. The required data were collected monthly from Damavand County’s agricultural and meteorological organizations in a time span ranging between 2012 and 2016. Given the flexibility of copula approach and its high accuracy in measuring dependency structure, this method was employed to account for joint distribution function and to measure expected loss. The results indicated that a strong dependency exists between dairy cow yield and temperature-humidity index, and this dependency can be better explicated through negative rotating Clayton index than any other copulas. The premium amount for each dairy cow has been calculated as 610650 Rials at 100 percent coverage level. Additionally, the expected loss resulted from heat stress at the 100 percent coverage level has been calculated as 42 kilograms within a month for each dairy cow. Considering the total number of dairy cows in the town, i.e. 2207 cows, the total loss resulted from heat stress has been calculated as 92694 kilograms and over 1.2 billion Rials within a month. With regard to the great loss resulted from heat stress and the importance of milk in the health of societies, it is recommended that the officials and policy-makers devote a particular attention to designing this insurance system throughout country.

کلیدواژه‌ها [English]

  • Dairy Cows
  • Damavand
  • Temperature-humidity index
  • Weather-based index insurance
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