ABD ticaret politikası belirsizlikleri ile küresel emtia fiyatları ilişkisi: asimetrik ve dinamik asimetrik nedensellik testlerinden kanıtlar

Abstract

Bu çalışma ABD ticaret politikası belirsizlikleri (TPU) ile seçilmiş emtiaların küresel fiyatları arasındaki ilişkiyi incelemeyi amaçlamaktadır. Analize dâhil edilen emtialar, kendi gruplarında uluslararası ticarette öne çıkan ürünler arasından seçilmiştir. Gıdayı temsilen şeker ve soya, enerjiyi temsilen petrol ve doğal gaz, kıymetli madenleri temsilen altın ve gümüş, metalleri temsilen bakır ve alüminyum kullanılan emtialardır. Çalışma 1990M01-2025M04 dönemine ait aylık verileri kapsamaktadır ve araştırma dönemi mevcut değişkenler için en yüksek gözlem aralığını sunacak biçimde seçilmiştir. Değişkenler arasındaki ilişki Hatemi-J asimetrik Granger nedensellik ve Hatemi-J dinamik asimetrik Granger nedensellik yaklaşımı kullanılarak incelenmiştir. Değişkenler arasındaki asimetrik ilişkilerin ele alınan dönem boyunca sabit olduğunu varsayan Hatemi-J asimetrik nedensellik bulgularına göre, ABD ticaret politikası belirsizlikleri ile küresel emtia fiyatları arasında Granger nedenselliğinin olmadığı gözlemlenmiştir. Dinamik asimetrik nedensellik bulgularına göre ise elde edilen ABD ticaret politikası belirsizliklerinin emtia fiyatları üzerindeki etkisinin dönemler ve emtia türleri itibarıyla farklılaştığını ve şokların yönüne bağlı olarak asimetrik özellik gösteren bir yapıda olduğunu göstermektedir. 2007-2008 küresel finansal kriz döneminde ABD ticaret politikası pozitif şoklarından pozitif altın fiyat şoklarına Granger nedenselliği doğrulanmaktadır. Bulgular, altın, gümüş, alüminyum, bakır, ham petrol, doğal gaz, soya ve şeker fiyatları ile ticaret politikası belirsizlikleri arasında zaman içinde değişen asimetrik nedensellik ilişkileri bulunduğunu ortaya koymaktadır. Ticaret politikası belirsizliği emtia piyasaları üzerinde tekdüze değil, emtiaya özgü ve heterojen etkiler yaratmaktadır. ABD ticaret politikası belirsizliklerinin küresel etkilere sahip olabileceği emtia fiyatları bağlamında doğrulanmaktadır. Bu çerçevede, çalışmanın politika önerileri, politika yapıcıların ve piyasa aktörlerinin değişen koşulları dikkate alması, emtia piyasalarındaki hareketliliği değerlendirirken belirsizliklerin niteliğini, yönünü ve politika yapıcıların belirsizliklerden kaynaklı fiyat şoklarının iç fiyatlara geçişkenliğini azaltacak tedbirler almaları çalışmanın politika önerilerini oluşturmaktadır.

Keywords

• Ticaret politikası belirsizliği
• emtia fiyatları
• asimetrik nedensellik
• dinamik nedensellik
• küresel emtia piyasaları

Supporting Institution

YOKTUR

Ethical Statement

Çalışma boyunca etik kurallara uyulmuştur.

Thanks

YOK

U.S. trade policy uncertainty and global commodity prices: evidence from asymmetric and dynamic asymmetric causality tests

Abstract

This study examines the relationship between US trade policy uncertainty (TPU) and the global prices of selected commodities. The commodities included in the analysis were selected from among the products that stand out in international trade within their respective groups. These include sugar and soy representing food, oil and natural gas representing energy, gold and silver representing precious metals, and copper and aluminum representing metals. The study covers monthly data from 1990M01 to 2025M04, and the research period was chosen to provide the highest possible observation interval for the variables. The relationship between the variables was examined using the Hatemi-J asymmetric Granger causality and Hatemi-J dynamic asymmetric Granger causality approaches. According to the Hatemi-J asymmetric causality findings, which assume that asymmetric relationships between variables remain constant throughout the period under consideration, no Granger causality was observed between US trade policy uncertainties and global commodity prices (GCP). According to the dynamic asymmetric causality findings, the impact of US TPU on commodity prices varies across periods and commodity types, exhibiting asymmetry depending on the direction of shocks. Granger causality is confirmed in the 2007-2008 global financial crisis, where positive US trade policy shocks led to positive gold price shocks. The findings reveal time-varying asymmetric causal relationships between gold, silver, aluminum, copper, crude oil, natural gas, soybean, and sugar prices and trade policy uncertainties. Trade policy uncertainty creates not uniform but commodity-specific and heterogeneous effects on commodity markets. The potential for global impacts from US trade policy uncertainties is evident in commodity prices. In this framework, the study's policy recommendations suggest that policymakers and market actors consider changing conditions, assess the nature and direction of uncertainties when evaluating volatility in commodity markets, and take measures to reduce the pass-through of price shocks caused by uncertainties into domestic prices.

Keywords

• Trade policy uncertainty
• commodity prices
• asymmetric causality
• dynamic causality
• global commodity markets

Supporting Institution

NONE

Ethical Statement

Ethical guidelines were followed throughout the study.

Thanks

NONE

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