2018 Volume 19 Issue 2 Pages 171-193
Though a bridge was built between isolated islands, it sometimes happens that the population of the island continues decreasing. The life of islanders becomes convenient by bridging. However, they do not continue living in the island if they do not have utility for residence in there. In this paper, by an economic theory we perform analysis of islanders to choose a place of residence. We deal with an environmental factor and a mental factor as two axes in the theory of utility to choose a place of residence. And we use indifference curve to examine utility of the islander on the anteroposterior time when a bridge is built. Furthermore, we examine optimization about the consciousness of the islander with bridging. We should check weak Pareto optimum solutions of the time well. A method for him to continue living in the island is shown in weak Pareto optimum solutions. As an example, we take up Ikema-jima and Kurima-jima in the Miyako-jima region, Okinawa prefecture. In addition, we consider about the prospects Irabu-jima and Shimojishima where Irabu Ohashi was crosslinked to Miyako-jima.