تاثیر استراتژی‌های تنوع درآمدی بر قدرت بازاری نظام بانکی

بانک‌ها، یکی از مهم‌ترین نهادهای بازار پول و سرمایه، نقش ارزنده‌ای در توسعۀ اقتصادی دارند. رشد پرشتاب اقتصادی و افزایش رقابت بین بانک‌ها در تخصیص بهینۀ منابع مالی باعث شده است که قدرت بازاری نظام بانکی اهمیت زیادی داشته باشد. از این ‌رو بانک‌ها بر آن هستند که با افزایش خلاقیت در استفاده از استراتژی‌های تنوع‌بخشی سپرده‌ها و متقاضیان تسهیلات بانکی بیشتری جذب کنند. هدف از این پژوهش بررسی تاثیر استراتژی‌های تنوع درآمدی بر قدرت بازاری نظام بانکی است. به این ترتیب داده‌های 20 بانک در ایران طی دورۀ زمانی 1398 1393 از صورت‌های مالی و یادداشت‌های پیوست جمع‌آوری شد. روش برازش پژوهش حاضر مدل گشتاور تعمیم‌یافته (gmm) است. قدرت بازاری بانک‌های موردبررسی از طریق شاخص لرنر اندازه‌گیری برای رسیدن به این هدف از تابع هزینۀ مرزی ترانسلوگ استفاده‌ و سپس قدرت بازاری محاسبه شد. برای سنجش استراتژی‌های تنوع درآمدی از دو شاخص هریشمن هرفیندال تعدیل‌شده شامل تنوع درآمدی بهره‌ای(hhinoi)  و غیر بهره‌ای (hhinon) استفاده‌ شده است. نتایج حاکی از آن است که استراتژی تنوع درآمدی غیر بهره‌ای بر قدرت بازاری نظام بانکی تاثیر مثبت و معناداری دارد؛ اما تاثیر استراتژی تنوع درآمدی بهره‌ای بر قدرت بازاری تایید نشده است.

The Effects of Income Diversification on Market Power in the Iranian Banking System

The purpose of this research was to investigate the effects of income diversification strategies on market power in Iranian banking system during the period of 20152020. The fitting method of the present study was the Generalized Method of Moments (GMM) model. Market power in banking system is measured by the Lerner index using the Translog stochastic frontier cost function. Two adjusted HerfindahlHirschman indices are used to measure income diversification strategies, including interest and noninterest income diversifications. The results showed that the noninterest income diversification strategy had a significant positive effect on market power in the banking system; however, the effect of the interest income diversification strategy on the market power was not confirmed. IntroductionIn recent years, one of the most important issues considered by researchers in industrial economics in the field of banking is analysis of the interbank market structure, market power of banking system and impacts of internal and external factors that have been widely used by policy makers and managers. It helps the banking industry to become more competitive. On the other hand, it can be seen that the banking industry has faced fundamental, rapid, and complex changes, including mergers, acquisitions, structural reforms, deregulation, and increasing competition. Many commercial banks have been pursuing income diversification strategies for maintaining their positions in the market in response to increasing competition. In fact, the competition between financial markets for optimal allocation of financial resources has attracted more depositors towards banks. It has made banks increase their banking facilities for applicants by increasing creativity via various tools. One of the most widely used diversification strategies is income diversification. The income structure includes the two types of interest and noninterest incomes. The structure of interest income includes the lending and traditional activities of banks, while that of noninterest income consists of fee income, commission, foreign exchange income, etc. There are few and contradictory studies on the relationship between the market power of banking system and diversification strategies. Given the contradictory points of view, this question will be raised: What effects do the income diversification strategies have on the market power of banking system in the Iranian banking industry?   Method and DataThe sample of this study included all the banks in the Iranian banking network operating in Iran during the period of 20152020. For this purpose, the required information of 20 banks was collected from their financial statements shown in Codal.ir website. The economic data were also extracted from the Central Bank website. The method used in this research was the Generalized Method of Moments (GMM). In this model, the dependent variable is added with an interval on the right side of the model, which leads to explaining the dynamic effects in the model. The estimated compatibility of the GMM is measured by Sargan test. FindingsFirst, to determine the choice of method between the Pool and Panel or the Fixed and Random Effects method, the Chow test was performed. The results showed that the value of FLimer statistic was 2.38 and its significance level was 0.0050. Therefore, the panel data were accepted. The Hausman test was then used to distinguish the fixed effects versus random effects. The result of this test was 32.31 ƛ2 and its significance level was 0.0001, which indicated that the model had to be estimated by using the fixed effects. In the next step, the GMM was fitted. The results showed that the variable of market power or competition with one lag had a significance level of less than 0.05. Hence, it had a positive and significant effect on the dependent variable (0.055(. The results also revealed that the noninterest income diversification with a coefficient of 0.21 and significance level of less than 0.05 had a positive and significant impact on the market power of the banking system (0.0094). The findings showed that all the control variables, except for the firm size, had a positive and significant effect on the market power of the banking system. Conclusion and discussion In this study, the effects of income diversification strategies on the market power of banking system were investigated in the Iranian banking industry during the period 13932014. The results demonstrated that noninterest income diversification had a positive and significant effect on the competition and market power of the banking system. However, the effect of interest income diversification on the market power of the banking system was not confirmed. It could be argued that commercial banks could create values for themselves based on noninterest income diversification by providing extensive financial services to customers and motivating them to use them so as to create the favorable market power and gain a competitive advantage. To strengthen this strategy, it is suggested that policymakers and legislators provide a better environment for foreign exchange by formulating and approving facilitative policies and creating the necessary infrastructure to cooperate with other banks in the neighboring countries. Banks can earn noninterest income by updating their services and coming up with new and innovative ideas to provide new services and strengthen their competitive positions in banking system. In the future research, the effects of various diversification strategies on market power in the developing and developed countries can be assessed and compared.