Panel Regression Analysis of Crop Production in Türkiye

Öz

In this study, the export quantities of 54 plant-based agricultural products produced in Türkiye during the period 2007–2019 were analyzed using panel data methods. The effects of production, imports, the degree of self-sufficiency, and human consumption per capita on exports were investigated. Prior to model estimation, multicollinearity, slope homogeneity, cross-sectional dependence, and panel unit root assumptions were examined. Three alternative panel data models: fixed-effects, random-effects and pooled ordinary least squares models were estimated. Among the models, random-effects model was selected based on the model selection test procedure. The results indicated that imports, the degree of self-sufficiency, and human consumption per capita had significant positive effects on exports, whereas the effect of production was not statistically significant. The panel causality analysis revealed a unidirectional causal relationship from production to exports and from exports to imports, while bidirectional causality was identified between exports and the degree of self-sufficiency, between exports and human consumption per capita, and between exports and the imports.

Anahtar Kelimeler

• Panel Data Analysis
• Agricultural Exports
• Panel Causality
• Random Effects Model

Türkiye'de Bitkisel İhracatın Panel Regresyon ile Analizi

Öz

Bu çalışmada, 2007-2019 yılları arasında Türkiye’de üretilen 54 bitkisel ürünün ihracat miktarları panel veri yöntemleri dikkate alınarak analiz edilmiştir. Üretim, ithalat, yeterlilik derecesi ve kişi başına tüketimin ihracat üzerindeki etkileri araştırılmıştır. Model tahmininden önce çoklu bağlantı, panel homojenliği ve yatay kesit bağımlılığı ve panel birim kök varsayımları incelenmiştir. Verilere üç panel veri modeli: sabit etki, rastgele etki ve toplanmış olağan en küçük kareler modelleri uygulanmış, model seçim test prosedürüne göre de rastgele etkiler modeli seçilmiştir. Sonuçlar, ithalatın, kendine yeterlilik düzeyinin ve kişi başına insan tüketiminin ihracat üzerinde anlamlı ve pozitif etkilerinin olduğunu, üretimin etkisinin ise istatistiksel olarak anlamlı olmadığını göstermiştir. Panel nedensellik analizi, üretimden ihracata ve ihracattan da ithalata doğru tek yönlü bir nedensellik ilişkisi ortaya koyarken; ihracat ile yeterlilik derecesi arasında, ihracat ile kişi başına tüketim arasında ve ihracat ile ithalat arasında da iki yönlü nedensellik ilişkisi olduğu saptanmıştır.

Anahtar Kelimeler

• Panel Veri Analizi
• Tarımsal İhracat
• Panel Nedensellik

Kaynakça

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