The Determinants of Net Interest Margin in the Turkish Banking Sector: Does Bank Ownership Matter?

2025-06-04

AI Summary

This study investigates the determinants of net interest margins (NIMs) of Turkish commercial banks from 2001 to 2012, with particular attention to how bank ownership structure—foreign, state-owned, or privately owned—moderates these relationships. Using bank-level panel data, we employ fixed-effects regressions and stratified estimations to identify heterogeneous effects across ownership types. Our analysis reveals, for the first time, that the impacts of credit risk, bank size, market concentration, and inflation on NIMs are significantly ownership-contingent, whereas variables such as operational diversification exhibit homogeneous effects across ownership categories. Key drivers of NIMs include credit risk, operating costs, and operational diversification; higher efficiency and greater price stability are associated with lower NIMs. The findings robustly confirm ownership structure as a critical moderating institutional factor, offering a novel institutional perspective on NIM formation in emerging-market banking systems.

Technology Category

• Game Theory and Economic Paradigms: Imperfect Information
• Multiagent Systems: Other Foundations of Multi Agent Systems
• Reasoning under Uncertainty: Other Foundations of Reasoning under Uncertainty

Application Category

• Social Networks and Social Media: Social media analysis through the lenses of networks
• Web Mining and Content Analysis: Bridging structured and unstructured data
• Economics, Online Markets and Human Computation: Incentives in network design for Web infrastructures and ecosystems

Abstract

This research presented an empirical investigation of the determinants of the net interest margin in Turkish Banking sector with a particular emphasis on the bank ownership structure. This study employed a unique bank-level dataset covering Turkey's commercial banking sector for the 2001-2012. Our main results are as follows. Operation diversity, credit risk and operating costs are important determinants of margin in Turkey. More efficient banks exhibit lower margin and also price stability contributes to lower margin. The effect of principal determinants such as credit risk, bank size, market concentration and inflation vary across foreign-owned, state-controlled and private banks. At the same time, the impacts of implicit interest payment, operation diversity and operating cost are homogeneous across all banks.

Problem

• Analyze determinants of net interest margin in Turkish banks
• Examine impact of ownership structure on banking margins
• Identify key factors like credit risk and operation diversity

Innovation

• Empirical investigation of net interest margin determinants
• Bank-level dataset analysis for Turkish banking sector
• Comparison of determinants across different bank ownerships