우리나라 은행산업의 효율성에 관한 실증분석

Abstract

Korea financial institutions experienced substantial changes in the last 10 years. Fiercer competition among both banks and non-bank financial intermediaries, technological progress, reduced information costs and ongoing deregulation in the wake of the foreign currency crisis led to substantial changes in numerous financial systems. Although the health of the Korea banking system has improved, its profitability remains weak. As net interest margins continue to decline and remain below those in other developed countries, enhancing core profitability remains an important challenge for banks. There has been relatively abundant academic research undertaken on the profitability and cost efficiency of Korean bank, especially for the post-1997 period. Most studies have focused on the use of parametric and non-parametric techniques to analyse cost and overall technical efficiency of Korean banks. This paper utilizes data for the period 1998-2008 to offer a fresh perspective on the cost and overall efficiency of Korean banks. This study employed non-parametric approaches, which were the Data Envelopment Analysis (DEA) and Malmquist Production Index similar to most previous studies. This study also employs parametric approach, which are the Type Ⅰ and Type Ⅱ Tobit analysis in contrast to the previous studies. The DEA is a linear programming technique for evaluating performance and benchmarking in a multivariate setting. The methodology uses information on the input-output combination of individual entities to construct an efficiency frontier enveloping the data. This frontier is then used to measure the efficiency of the individual entities relative to a benchmark entity, chosen by the model. The DEA produces efficiency estimates without a priori functional restrictions on the underlying production process. By duality, the DEA can be used to assess either cost or revenue efficiency, depending on the setup. Cost efficiency looks at how banks use their inputs to produce a given level of outputs. Revenue efficiency examines how much output banks can produce using the same inputs. This paper analyzes the efficiency and profitability of Korean banks from 1998-2008. This paper uses data envelopment analysis to analyze the cost and revenue efficiency of Korean banks. One of the crucial issue to build a model for the assessment of banking efficiency is th identification of appropriate inputs and output. This issue is not straightforward and an extended and unresolved controversy remains in the literature. The two approaches most often used are the production and intermediation approaches, although other approaches such ad the asset, user-cost and valued added approaches are also well established in the banking literature. The production approach emphasizes the operational activity and thus banks are primarily viewed as providers of services to customers. Under the intermediation approach financial institutions are views as primarily intermediating funds between savers and investors, Although these approaches can offer valuable guidelines regarding the definition of appropriate banking models to asses certain objectives, the empirical studies often emphasize particular issues of concern to the organizations, such that the choice of inputs and output of banking studies is very much influenced by the analysts' view of the banking activity, the issues under analysis, and the availability of data. Here, the framework assumes that banks use two inputs to produce two outputs. The outputs consist of loans and deposits. The inputs include number of employees or number of branches and fixed assets. This paper obtained data from the balance sheet and profits and loss accounts of the FISIS (Financial Statistics Information System) that the Financial Supervisory Service reported. When the number of emplyees (number of branches) and fixed assets are utilized input factors and loaned money and deposits as output factors, inefficiency of regional banks is large, and it was showed that the number of branches is the important question rather than the number of employees. Such results are similar to those of the case when only loaned money is considered as output factor, but when only deposits are considered as output factor, there are not any significant differences in efficiencies between regional banks and commercial banks. I employed Malmquist production index with the efficiency of the DEA models. The results showed that total productivity increased in all the factor combinations, but as technological efficiency decreased, banks decided frontier, indicating the expanded gap between leading banks and inefficient banks due to reorganization of banking markets. This study decomposed Malmquist productivity index into two components, namely, efficiency change and technical change and found that most of growth of the total factor productivity was due to the technical change rather than the efficiency change. As technological efficiency decreased, however, the leading banks decided technological renovation for management improvement and then moved to efficient frontier. It has widened the efficiency gap between leading decision making units and inefficient banks. The Tobit analysis including type Ⅰ and type Ⅱ models was also employed to regress the variable on the relevant explanatory variables. The censored regression technique that the dependent variable was the truncated technical efficiency based on the constant returns to scale over the 2003-2008 period showed that ROA had negative effects on efficiency. The sign and significance of ROA and BIS depended on which model was employed and which input-output combination was used. BIS had strong negative relations with efficiency when loans or deposits were used as the output factor, while asset was positively significant in the deposits only. The efficiency analysis presented in this paper, of course, uncovered the existence of considerable inefficiencies may be the fact that cost efficiency is not the sole driver in the management of commercial activity of banks. Other targets, related to marketing success, quality of service, and financial gains from the intermediation activity may be given higher priority over the achievement of cost efficiency. This study also tried to cover all the presently available models, but the results were not so satisfactory as to explain and predict the competitiveness and efficiencies of Korean banking system accurately. This menas that there are many other aspects to be considered in treating DEA besides those attended to in this paper. A more extensive examination is left to a next paper.