Empirical evaluation of structure-conduct-performance paradigm as applied to the Iranian Islamic banking system

Purpose - This paper aims to investigate the impact of market structure and market share on the performance of the Islamic banks operating in the Iranian banking system based on the structure-conduct-performance (SCP) paradigm. Design/methodology/approach - The Iranian Islamic banking system’s market structure is evaluated by using the econometrics method to test the validity of the traditional SCP paradigm. For this purpose, the authors estimate a simple regression model that is consisted of several independent variables, such as the market share, bank size, real gross domestic product, liquidity and Herfindahl-Hirschman index as a proxy variable for concentration and one dependent variable, namely, the profit as a proxy for performance. The panel data includes a data sample of 22 Islamic banks operating from 2006 to 2019. Data are extracted from the balance sheet of Islamic banks and the time-series database of the Central Bank of Iran and World Bank. Findings - The study’s findings indicate that both concentration and market share have a positive impact on the performance of banks in the Iranian Islamic banking system. This result is contradicted with both traditional SCP and efficient structure hypotheses; however, it confirms the existence of oligopoly or cartel in the Iranian Islamic banking system that few banks try to gain the highest share of profit and maintain their market share by colluding with each other. This result is in contradiction with other research studies about the market structure in the Iranian banking system that claimed that banks in Iran operate under monopolistic competition. In addition, it shows that the privatization of some banks in Iran does not improve and help competition in the Iranian banking system. Originality/value - This paper is a pioneer empirical study analyzing the market structure, concentration and collusion based on the SCP paradigm in Iranian Islamic banking. The results of the study support the existence of collusive behavior among the Islamic bank in Iran that is not aligned with Sharia. This study clearly shows the difference between ideal Islamic banking and Islamic banking in practice in Islamic countries. This clearly indicates that only prohibiting some operations like receiving interest, gambling and bearing excessive risk is not enough. In fact, the Islamic banking system should be based on the Sharia rule in all aspects and much more modification and study have to be done to achieve an appropriate Islamic banking system. These possible modifications to overcome the issues of cartel-like market structure and collusive behavior in the Iranian Islamic banking system include making the Iranian banking system more transparent, letting foreign banks enter the Iranian banking system and minimizing the government intervention in the Iranian banking system.