نوع مقاله : مقاله پژوهشی

نویسندگان

1 محقق پسا دکتری، صندوق ملی حمایت از پژوهشگران و فناوران کشور، تهران

2 دانشجوی دکتری مالی دانشکده علوم اداری اقتصاد دانشگاه اصفهان

چکیده

قیمت نفت خام یکی از مهم‌ترین شاخص‌های اقتصاد است که سیاست‌گذاران، تولیدکنندگان، مصرف‌کنندگان و مشارکت‌کنندگان در بازار انرژی رفتار آن را رصد می‌کنند. قیمت نفت مسیر و رفتار خود را با توجه به شرایط اقتصادی تغییر می‌دهد و به همین دلیل بسیار متلاطم است. دانش پژوهندگان، سیاست‌گذاران و مشارکت‌کنندگان از میزان اثرگذاری بحران‌ها بر بازار نفت کنترل پیامدهای منفی آن را به شیوه بهتری فراهم می‌کند. بررسی‌ها نشان می‌دهد که درنتیجه بحران‌های مختلف پایداری تلاطمی بازار نفت بسیار بالاست. بنابراین بررسی فرضیه وجود ریشه واحد در شوک‌های تلاطمی این بازار منطقی است. در پژوهش حاضر ماندگاری بلندمدت شوک‌های تلاطمی ناشی از بحران همه‌گیری کووید-19 در بازار نفت برنت و WTI که دو معیار تعیین قیمت‌های جهانی نفت هستند با استفاده از آزمون پیشنهادی توسط لی و یو (2010) بررسی می‌شود. نتایج این پژوهش نشان‌دهنده وجود ریشه واحد در تلاطم بازار نفت است. بنابراین بازار نفت و فضای اقتصادی به شکل طولانی‌مدت درگیر اثرات این بحران است. این موضوع می‌تواند اثرات چشمگیری بر درآمدهای کشورهای صادرکننده و سرمایه‌گذاران در حوزه نفت خام داشته باشد. به این ترتیب بازیگران این بازار و دولت‌ها باید با دقت بیشتری پیامدهای این بحران را ارزیابی کنند.

کلیدواژه‌ها

موضوعات

عنوان مقاله [English]

Unit Root Volatility Due to Covid-19 Epidemic in the Crude Oil Market

نویسندگان [English]

  • mojtaba rostami 1
  • Alireza Najjarpour 2

1 Postdoctoral Researcher, Iran National Science Foundation, Tehran, Iran

2 Ph.D. Student of Finance, Faculty of Administrative Science and Economics, University of Isfahan, Isfahan, Iran

چکیده [English]

The price of crude oil is one of the most important indicators of the global economy, which is monitored by policymakers, producers, consumers, and participants in financial markets. Oil prices are changing course depending on economic conditions, which is why it is so volatile. The knowledge of researchers, policymakers, and stakeholders about the impact of crises on the oil market provides better control over its negative consequences. Studies show that as a result of various crises, the Volatility Persistence of the oil market is very high. Therefore, it makes sense to consider the hypothesis of a unit root in the Volatility shocks of this market. In the present study, the long-term Volatility Persistence shocks due to the Covid-19 epidemic crisis in the Brent and WTI oil markets, which are the two criteria for determining global oil prices, are investigated using a test proposed by Lee and Yu (2010). The results of this study indicate the existence of a unit root in oil market turbulence. Therefore, the oil market and the economic climate are long-term affected by the effects of this crisis. This can have a significant impact on the revenues of exporting countries and investors in the crude oil sector. Thus, market players and governments need to assess the consequences of this crisis more carefully

کلیدواژه‌ها [English]

  • Unit Root
  • Volatile Persistence
  • Crude Oil Price
  • Brent oil
  • WTI oil
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