Competition-Stability Relationship in Islamic Banks: Random Forest Algorithm Findings

Year 2026, Volume: 13 Issue: 1, 153 - 177, 13.01.2026

Mustafa Çelik

https://doi.org/10.17541/optimum.1762662

Abstract

The competitive landscape of the Turkish Islamic banking sector has undergone a significant transformation in recent years. This has made the sector an interesting research area for testing the competition-stability relationship, a topic frequently discussed in banking literature. To this end, the study aims to examine the competition-stability relationship in the Turkish Islamic banking sector. For this purpose, quarterly sectoral data covering the period from 2009Q1 to 2025Q1 are analyzed using the Random Forest algorithm. According to the analysis results, insufficient/low competition in the Islamic banking sector increases the sector's fragility. These vulnerabilities manifest themselves in indicators such as credit risk, capital adequacy, and credit appetite. It is observed that there is no relationship between competition and stability indicators such as liquidity, foreign exchange position, and profitability. The findings highlight the importance of implementing policies that encourage new bank entries and limit market concentration in the participation banking sector. Moreover, the findings indicate that surpassing certain threshold levels of competition leads to differentiated effects on financial stability indicators. Therefore, it is recommended that regulators consider competition as a strategic policy instrument, taking optimal levels into account.

Keywords

Islamic Banking , Competition , Financial Stability , Random Forest

Katılım Bankalarında Rekabet-İstikrar İlişkisi: Rastgele Ormanlar Algoritması Bulguları

Abstract

Türk katılım bankacılığı sektörünün rekabet yapısı, son dönemde önemli bir dönüşüm geçirmiştir. Bu durum, bankacılık literatüründe zaman zaman yer bulan rekabet-istikrar ilişkisinin test edilmesi için sektörü ilgi çekici bir araştırma alanı haline getirmiştir. Çalışma bu kapsamda, Türkiye’deki katılım bankacılığı sektöründe rekabet ve istikrar arasındaki ilişkiyi incelenmeyi amaçlamaktadır. Bu amaç doğrultusunda 2009:Ç1-2025:Ç1 arası dönemi kapsayan çeyreklik sektör verileri, Random Forest (Rastgele Ormanlar) algoritması kullanılarak analiz edilmiştir. Analiz sonuçlarına göre, katılım bankacılığı sektöründe eksik/düşük rekabet koşulları, sektörün kırılganlığını artırmaktadır. Söz konusu kırılganlıklar, kredi riski, sermaye yeterliliği ve kredi iştahı gibi göstergelerde kendini göstermektedir. Likidite, döviz pozisyonu ve kârlılık gibi istikrar göstergeleri ile rekabet arasında ise bir ilişkinin bulunmadığı görülmektedir. Elde edilen sonuçlar, katılım bankacılığı sektöründe yeni banka girişlerini teşvik eden ve yoğunlaşmayı sınırlayan politikaların uygulanmasının önemine işaret etmektedir. Ayrıca, bulgular rekabet düzeyinde belirli eşik değerlerin aşılmasıyla istikrar göstergelerinde farklılaşan etkilerin ortaya çıktığını göstermektedir. Bu sebeple düzenleyicilerin rekabeti, optimal seviyeleri gözeten stratejik bir politika aracı olarak ele alması önerilmektedir.

Keywords

Katılım Bankacılığı , Rekabet , Finansal İstikrar , Rastgele Ormanlar

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