Ekonomik Şoklar Altında Petrol-Gıda Fiyat Dinamikleri: Yapısal Bir VECM Yaklaşımı

Abstract

Bu çalışma, Ocak 1990 ile Ağustos 2012 dönemine ait aylık zaman serisi verilerini kullanarak, küresel ham petrol fiyatları ile gıda fiyatları arasındaki dinamik ilişkiyi Yapısal Vektör Hata Düzeltme Modeli (VECM) kapsamında incelemektedir. FAO Gıda Fiyat Endeksi ile IMF Ham Petrol Fiyat Endeksi veri seti olarak kullanılmış; serilerin durağanlığı ADF, PP, KPSS ve Zivot-Andrews birim kök testleriyle analiz edilmiştir. Bilgi kriterlerine göre optimal gecikme uzunluğu belirlendikten sonra Johansen eşbütünleşme testi uygulanmış ve uzun dönemli eşbütünleşme ilişkisi tespit edilememiştir. VECM bulguları, petrol fiyatlarındaki %1’lik artışın gıda fiyatlarını uzun vadede %0,506 oranında artırdığını, kısa vadede ise gıda fiyatlarının petrol fiyatları üzerinde Granger nedenselliği taşıdığını göstermektedir. Bulgular; enerji maliyetleri, biyoyakıt talebi ve lojistik giderler yoluyla oluşan çift yönlü geçişkenliğe işaret etmektedir. Bu çalışma, gelişmekte olan ülkelerde fiyat istikrarı ve gıda güvenliği hedefleri doğrultusunda entegre piyasa izleme sistemleri, stratejik rezerv mekanizmaları ve esnek enflasyon hedeflemesi gibi makroekonomik politika araçlarının birlikte uygulanmasının önemine dikkat çekmektedir. Ayrıca, gelecekteki araştırmalar için genişletilmiş veri kapsamı ve doğrusal olmayan modellerle analiz önerilmektedir.

Keywords

• Ham Petrol Fiyatları
• Gıda Fiyatları
• Vektör Hata Düzeltme Modeli
• Granger Nedensellik
• Yapısal Kırılmalar

Oil-Food Price Dynamics under Economic Shocks: A Structural VECM Approach

Abstract

This study investigates the dynamic relationship between global crude oil prices and food prices using monthly time series data from January 1990 to August 2012 within the framework of a Structural Vector Error Correction Model (VECM). The FAO Food Price Index and the IMF Crude Oil Price Index are employed as the primary data sources. The stationarity of the series is tested using ADF, PP, KPSS, and Zivot-Andrews unit root tests. After determining the optimal lag length through information criteria, the Johansen cointegration test is applied, but no long-run cointegrating vector is identified. Nevertheless, VECM results indicate that a 1% increase in oil prices leads to a 0.506% rise in food prices in the long run, while food prices have a Granger-causality effect on oil prices in the short run. These findings highlight a bidirectional transmission mechanism through energy costs, biofuel demand, and logistics expenses. The study emphasizes the critical role of coordinated policy tools such as flexible inflation targeting, strategic reserve mechanisms, and integrated market surveillance systems in ensuring food security and price stability in developing economies. Future research should consider extended datasets and nonlinear modeling approaches to capture regime-dependent dynamics more effectively.

Keywords

• Crude Oil Prices
• Food Prices
• Vector Error Correction Model
• Granger Causality
• Structural Breaks

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