본 연구에서는 국내 은행 및 카드사의 실제 개인신용 미시자료를 이용하여 금융회사가 부정적 및 긍정적 신용정보를 공유함에 따라 실현되는 경제적 효과를 실증 분석하였다. 분석 결과 금융회사 는 자사정보만을 이용하거나, 은행연합회를 통해 공유되고 있는 기초정보만을 활용한 부분정보 모 형에 비해, 긍정적 정보까지 모두 활용하는 경우 신용스코어 모형의 변별력이 유의하게 높아지며, 동일 승인율 하 불량률의 감소, 동일 불량률 하 승인율 및 여신규모(exposure)의 확대, 고객별로 차별화된 금리의 적용 등을 통해 위험관리의 실효성과 수익성을 제고할 수 있는 것으로 분석되었다. 이러한 결과는 소비자 입장에서도 정보의 비대칭성 완화에 따른 차입금리 하락과 여신 접근성 확대로 경제적 후생이 높아질 수 있음을 시사한다. 나아가 본 연구는 현실적으로 대형사와 중형사 간 정보 보유량이 상이함을 감안하여, 긍정적 정보 공유의 효과가 금융회사의 규모에 따라 차별적으로 실현되는지 여부를 분석하였다. 분석 결과 통계적 성능지표의 향상, 동일 승인율 하 불량률 및 불량고객수 감소율, 동일 불량률 하 승인율 확대 효과 등, 모든 측면에서 대형사와 중형사간 긍정적 정보 활용의 효과가 유의한 차이 없이 실현되고 있는 것으로 나타났다. 이러한 결과는 일반 적인 예상과는 달리 정보량이 많은 대형사가 정보공유에 따라 일방적으로 손해를 보는 구조가 아 님을 의미한다. 이러한 현상은 우리나라의 경우 대형 금융회사의 고객일지라도 타사와 중복거래를 하고 있는 고객이 많기 때문인 것으로 판단되며, 대형사 또한 자사고객에 대한 타사의 정보를 활 용하기 위해 적극적으로 정보공유에 나설 유인이 존재함을 시사한다.

Currently in Korea, in addition to negative credit information such as loan default and arrears, positive credit information is also exchanged on a voluntary and reciprocal basis through private credit bureaus (CBs). This paper studies economic benefits of sharing negative and positive credit information realized by banks and credit card companies using individual consumer credit data of a large private credit bureau. We also investigate whether the degree of economic benefits that can be realized through positive information sharing is significantly different across financial companies with heterogeneous firm size. We find that, compared to the models based on each company`s own credit information or the basic and negative information compiled by the public credit registry, the performance of credit scoring models significantly improves when we utilize both negative information and positive information of credit bureaus. All statistical performance indicators such as Kolmogorov- Smirnov statistics, divergence, Gini index, and C-statistics improve significantly when positive information is utilized in addition to negative information for all sample banks and credit card companies regardless of their firm size. The improvement in discriminatory powers based on a wider set of credit information can produce significant economic benefits for financial companies. In our analysis of commercial banks, sharing positive credit information leads to a significantly lower default rate at each loan acceptance rate, and a higher loan acceptance rate and increased total exposure at each target default rate. We also obtained similar results for credit card companies. Hence, our results suggest that financial firms can substantially improve risk management capacity and enhance profitability by voluntarily sharing positive credit information. Our results also imply that positive information sharing can improve consumer welfare by alleviating asymmetric information problems as consumers` borrowing costs decrease and loan accessibility increases. We proceed to compare the benefits of positive information sharing across large and small financial companies. From every aspect such as statistical performance of credit scoring models, the degree of reduction in default rates and the number of defaulted obligors, and the increase in loan acceptance or card limit approval rates, we could not find significant differences in economic benefits realized across large and small financial companies. Hence, our results suggest that it is not necessarily a valid conjecture that large financial companies with a large customer base are hesitant to share their information voluntarily with small financial companies as their benefits are smaller relative to those of small companies. This finding reflects a notable feature of consumer credit markets in Korea. Namely, the customers of a large financial company tend to have multiple transaction relationships with other smaller financial companies. Hence, even large financial companies have a strong incentive to voluntarily share their positive credit information with smaller companies in order to obtain other companies` credit information on their own customers. Note that our empirical analysis assumes that the customer base of information sharing financial companies does not change subsequently as a result of credit information sharing. However, in reality, positive information sharing may increase competition and undermine profitability by lowering informational rents of financial companies. Hence, a financial company`s actual incentive to participate in the positive information sharing mechanism will depend upon the relative magnitude of economic benefits and costs resulting from enhanced risk management capacity and more intense competition. We leave this consideration of potential competition effects as a future research agenda.