MODELING AND FORECASTING GLOBAL AGRICULTURAL COMMODITY PRICES USING HYBRID MODELS

Öz

In recent years, rare events such as the COVID-19 pandemic and the Russia–Ukraine war have caused disruptions in global agricultural commodity supply chains, especially through supply and demand imbalances. As a result, unusual price fluctuations have been observed in commodity markets. In such periods, accurate modeling and forecasting of agricultural commodity prices is important to keep the agricultural sector sustainable for both national economies and individual investors. In this study, the performance of several methods used to model financial time series with rare and low-probability events is compared. These methods include the Generalized Autoregressive Conditional Heteroskedasticity (GARCH) model, the State Space Model (SSM), Long Short-Term Memory (LSTM) neural networks, and hybrid GARCH-LSTM models. The analysis uses weekly global agricultural commodity prices for wheat, sugar, cocoa, coffee, cotton, corn, soybean, and oats from March 2001 to December 2025. The results show that the State Space Model demonstrates significantly superior performance in both price modeling and future forecasting.

Anahtar Kelimeler

• Agricultural commodity prices
• Machine learning
• State space model
• Global rare events

Destekleyen Kurum

Eskisehir Osmangazi University Scientific Research Fund (ESOGU BAP)

Proje Numarası

FBA-2025-3333

Etik Beyan

No Need/Not Applicable

MODELING AND FORECASTING GLOBAL AGRICULTURAL COMMODITY PRICES USING HYBRID MODELS

Öz

Son yıllarda, dünyada COVID-19 pandemisi ve Rusya-Ukrayna savaşı gibi nadiren görülen olayların etkisiyle özellikle dünyadaki tarımsal emtia tedarik zincirlerinde arz-talep dengesizlikleri gibi aksaklıklar gözlemlenmiştir. Bu gelişmeler sonucunda emtia fiyatlarında olağandışı dalgalanmalar (volatilite) gözlemlenmiştir. Bu gibi durumlarda, tarım sektörünün hem ülke ekonomileri hem de bireysel yatırımcılar açısından sürdürülebilir olması için tarımsal emtia fiyatlarının modellenmesi ve gelecek tahmininin en az hata payı ile yapılması önem taşımaktadır. Nadiren görülen düşük olasılıklı olayları içeren finansal zaman serilerinin modellenmesinde ve gelecek tahminlerinin yapılmasında yenilik olarak genelleştirilmiş otoregresif koşullu değişen varyans (GARCH), durum uzay modeli (State Space Model, SSM), uzun kısa süreli bellek (Long Short-Term Memory, LSTM) yapay sinir ağları ve Hibrit GARCH-LSTM modellerinin performans karşılaştırmaları yapılmıştır. Bu projede, Mart 2001 ile Aralık 2025 tarihleri arasındaki dünya tarımsal emtia haftalık fiyatlarından; buğday, şeker, kakao, kahve, pamuk, mısır, soya ve yulaf fiyatları kullanılmıştır. Sonuç olarak, durum uzay modelinin (State Space Model), modelleme ve gelecek tahmini konusunda açık olarak iyi performans göstermiştir.

Anahtar Kelimeler

• Tarımsal Emtia Fiyatları
• Makine Öğrenmesi
• Durum Uzay Modeli
• Küresel Nadir Olaylar

Proje Numarası

FBA-2025-3333

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