Wireless telecommunication market in Korea has grown very dramatically recently and the number of wireless telecommunication subscribers is over that of wired telephone subscribers. Many researchers estimate that the wireless telecommunication market in Korea is approaching the level of saturation. Therefore, customer retention is a more important issue than the acquisition of new customers for wireless telecommunication service providers. Furthermore, with adoption of MNP (Mobile Number Portability), customers can easily change their wireless telecommunication service providers while retaining their original dialed number.
The main objective of this study is to construct a customer retention model by (1) extracting the statistically significant determinants that influence the out-bounding churn and in-bounding churn separately and (2) ranking the importance of sub-factors to minimize out-bounding chum and satisfy in-bounding churn customers.
This model is applied to one domestic wireless telecommunication service providers, "A", and the consequence of this study. The following observations have been identified:
(1) There are considerable discrepancies between the service satisfaction of out-bounding churn and customers remaining after MNP. This implies that customers who are less satisfied with the service show a higher tendency to change service providers, indicating that low service satisfaction is highly related to the out- bounding churn.
(2) Through the logistic regression analysis, appropriate service charges and supplementary services are statistically significant determinants of out-bounding churn while brand image and speech quality are statistically significant determinants of in- bounding churn. This shows that the significant determinants of out-bounding churn and in-bounding churn are different. Through discriminant analysis, it is shown that appropriate service charges influence the out-bounding churn more than supplementary services. It is also shown that speech quality is a more important factor than brand image for in-bounding churn.
(3) It is also indicated through a t-test that, in regards to speech quality, the degree of service satisfaction of remaining customers and the perception of in-bounding churn is different.
(4) Ranking the importance of sub-factors that could minimize out-bounding churn and satisfy in-bounding churn customers is done by pairwise comparison. In the case of speech quality, the importance of sub-factors is the quality of call sound, call connection, and call disconnection, in that order. Variety of fee types is the most important sub-factor of appropriate service charges and data service is the most important sub-factor of supplementary service.
Based on the findings, the customer retention strategy is suggested as follows:
$\bullet$ The wireless telecommunication service providers should consider the determinants of in-bounding churn and out- bounding churn separately to maximize the number of their customers after MNP is adopted.
$\bullet$ Service quality improvement is necessary not only to prevent out-bounding churn but also to satisfy in-bounding churn after they become subscribers.
As the technologies of wireless telecommunication are developed, a variety of fee types and data service is emphasized rather than basic voice services.
본 연구는 이동 전화 번호 이동성(Mobile Number Portability)시행 후, 이동통신 사업자들이 기존 가입자의 이탈을 방지하고, 타사 가입자의 가입 전환을 유도하기 위해 고려해야 할 영향 요인들을 실증적으로 분석하고 이에 따른 고객 유지 전략을 제시하고자 한다.
이러한 연구 목적을 달성하기 위해 기존 문헌 연구를 바탕으로 가입 전환 영향 요인들과 그 세부 요인들을 도출하여 In-bounding churn을 최대화 하고 Out-bounding churn을 최소화하는 연구 모형을 설정하였다. 기본적으로 서비스에 대한 만족도가 가입 전환에 영향을 미치는지 파악하기 위해 번호 이동성 시행 후 타 사업자로 가입 전환을 하고자 하는 고객과 그렇지 않은 고객 간의 만족도 차이를 분석 하였다. 그리고 In-bounding churn과 Out-bounding churn에 유의한 영향 요인들을 도출하기 위해서 로지스틱 회귀 분석(Logistic Regression Analysis)을 적용하였고, 영향 요인들의 차이성을 검증하기 위해 판별분석(Discriminant Analysis)을 실시하였다. 마지막으로 Out-bounding churn을 최소화하고 In-bounding churn고객이 서비스에 만족할 수 있도록 구체적으로 개선해야 할 가입 전환 영향 요인의 세부 요인들에 대한 중요도는 쌍대비교법(Pairwise Comparison)을 사용하여 도출하였다.
이러한 연구 모형을 국내 이동통신 사업자에게 적용하기 위해 현재 이동통신 가입자들과 전문가를 대상으로 2 번의 실증 분석을 하였다. 도출된 결과는 이동통신 사업자들이 번호 이동성 시행 후 현재 가입자들의 이탈을 최소화 하고, 타사 가입자들의 자사로의 가입 전환을 유도하기 위한 세분화되고 다양한 전략 수립의 근거를 제공할 것이다.
