변이할당분석을 이용한 광양항과 인천항의 수출구조 분석

Abstract

Shift-share analysis is a traditional tool for the measurement, comparison, and evaluation of interregional and sectoral performance. Its widespread use is explained by its simplicity and modest data requirements; it does not require primary data collection and its results are also relatively easy to assess and interpret. Since exports are a vital factor in the overall development of a port, some means of quantitatively assessing export changes must be developed. If shifts in exports can be isolated, they can be used to explain partially structural transformations in ports and to provide insight into possible future direction for port development. This study, therefore, uses a shift-share technique to isolate the various factors associated with export changes. The traditional shift-share model partitions the change of exports in a port into three effects: the national growth effect, the industrial mix effect and the regional share effect. The national growth effect attempts measure the change in exports in a port that would have occurred if its exports had grown at precisely the same rate as the national average. Hence, if a port grows at the same rate as the national average, it does not possess any comparative advantage in terms of resource endowments or human capital. The industrial mix effect associates the differential growth rate in exports between the region in question and the nation as a whole with the overall strengths or weaknesses of the relevant export sectors. Ideally, it is expected that a large proportion of a port’s exports should be concentrated in faster-growing industries. The regional share effect accounts for the differential change between a port and the nation. The regional share effect portrays the competitive position of a port in relation to the rest of the port. For instance, an export component that is growing faster in a port than its counterparts in the nation as a whole will add to the port’s overall growth relative to that of the nation, while a slower-growing component will bring forth an opposite effect. The export data used in this study are obtained from the Korea International Trade Association and consist of exports by two ports of 20 individual products. The particular product categories studied are at three-digit MTI (Ministry of Trade and Industry) level of disaggregation. The national growth effect for synthetic resin and steel plate-rolled products accounted for about 96 percent and 102 percent respectively of the increase in exports of Gwangyang Port or 3,685 and 4,226 million dollars respectively during the period under analysis. The fact that the industrial mix effects of the two products were negative−at 486 and 1,191 million dollars, respectively−can be interpreted to mean that Gwangyang Port’s main export products were growing slowly rather than rapidly. The regional share effects of the two products did not explain a large proportion of the change−at about 16 percent and 27 percent, respectively. The greatest regional share impact was in the steel plate-rolled product sector. The national growth effect of the automobile industry accounted for about 99 percent of the increase in export of Incheon Port or 3,378 million dollars, while that for the flat panel display only explained 1 percent or 100 million dollars. The regional share effect of flat panel display, however, explained a very large percentage of the change−88 percent or 12,238 million dollars−compared with automobiles, at 46 percent or 1,585 million dollars. The industrial mix effect of the two products was negative or explained only a small portion of the change.