항만 투자가 국가 경제에 미치는 기여를 추정하기 위해서는 항만 투자로 인한 항만 SOC 증가가 물동량에 어떠한 영향을 미치는 지 추정이 필요하다. 본 연구는 패널자료를 사용하는 고정효과모형을 통해 추정하여 1920년부터 2015년 96년간의 기간 중 일본 내 1,082개 항만을 대상으로 6개 부문으로 세분류된 항만자본스톡과 해상 물동량 간의 상관관계를 추정하였다. 본 연구의 실증분석 결과에 따르면, 컨테이너 부두 관련 항만 자본 스톡이 1.0% 증가하면 항만물동량은 0.15% 증가하고, 일반 부두 관련 항만 자본 스톡이 1.0% 증가 시 항만물동량은 0.09% 증가한다. 무엇보다 방파제·방파호안 등의 파제 시설 자본 스톡이 물동량에 높은 영향을 미치는 것으로 나타났는데, 파제 시설 관련 자본 스톡 1.0% 증가 시 해상 물동량은 0.32% 증가하는 것으로 추정되었다. 본 연구의 회귀 분석 결과는 항만투자로 인한 항만 SOC 증가는 물동량 확대로 이어질 수 있음을 보여주는 것으로, 장래 적극적인 항만투자가 필요함을 시사하고 있다.
Recently, Korea has been witnessing the emergence of some idle ports whose cargo-handling capacities are bigger than their sea traffic, frequently raising concerns over excessive port investments. Thus, it is important to find a logical explanation for whether investments in port social overhead capital(SOC) can ultimately contribute toward increasing the traffic volume of ports, even the nation's economic development. In this study, using the fixed effects model with panel data, we investigate the impact of port SOC on maritime traffic. In order to investigate the relationships between port SOC and maritime volume, panel data covering a period of 97 years and 1,082 ports was applied to a regression model. Panel data could be collected by collaborating with the Ministry of Land, Infrastructure, Transport and Tourism (MLIT). MLIT now periodically announces the SOC amount of Japanese ports. First, we followed the rules set by the MLIT, according to which the port SOCs was divided into six categories: “the development of new port", “the development of container berth", “the development of bulk berth", “the jetty facilities like breakwater", “the maintenance of port", and “the navigation facilities." Then, we performed the regression analysis by setting the maritime traffic as the dependent variable and the forementioned six categories as independent variables.
By applying the Hausman and LR tests, we could find that the fixed effect model is statistically more appropriate than the random effect model for this study. The primary results of this study in the fixed effect model are that the coefficients of “the development of container berth", “the development of bulk berth", “the jetty facilities" show a positive (+) impact on the dependent variable, the sea traffic. Contrarily, the coefficients of “the development of new port", “the maintenance of port", and “the navigation facilities" show a negative () impact. The coefficients of the development of container berth and the development of bulk berth show that the maritime traffic will increase by 0.15% and 0.09% if the SOC of the development of container berth or the development of bulk berth increase by 1%. The coefficient of the development of new port explains that if the SOC of the development of new port increases by 1.0%, the maritime traffic will decrease by 0.05%. In addition, the coefficients of the maintenance of port and the navigation facilities show that their elasticities for sea traffic are -0.06 and -0.09, respectively.
Especially, the coefficient of “the jetty facilities like breakwater" has a strong impact on maritime traffic. The result of the fixed effects model regression, indicates that the maritime traffic will increase by 0.32% when the SOC of the jetty facilities increase by 1.0%. Therefore, we can conclude that port authorities(like the Ministry of Maritime Affairs and Fisheries) find it appropriate to invest in port SOC including jetty facilities for increasing maritime traffic in the future.