日・米・タイのコメ生産費格差の時系列変化の要因分析

Abstract

Comparing the rice production cost among the three countries, it was found that the absolute differences between Japan on one hand and America and Thailand on the other had increased rapidly during the seventies but have stagnated during the eighties, and that Japan's production cost has become 16.9 times and 11.3 times higher than Thai's and America's respectively in 1988 as the Thai and American costs have decreased considerably during the late eighties. From the factor analysis of the changes in the relative cost differences between Japan arid America and between Japan and Thailand, it was found that the appreciation of yen contributed 56-81% of the changes during the research period. The declines in the Japanese rice productivity against American and Thai ones explain 58-78% of the changes in the relative cost differences during the same period. The relative declines in the factor prices in Japan against the other two countries have mitigated the increase in the relative cost differences by 36-44%. The relative cost differences was expected not to increase very much in the future. But since the current differences are very large, it is suggested that Japanese rice farm size must be increased, new technology must be developed and the factor markets must be made more competitive and efficient in order to decrease rice production cost.