Bovenberg and Mooij (1994) and others pointed out that the optimal taxation on goods with external diseconomy both collects revenue and also corrects the external diseconomy by the goods, and thus it is said that the tax has gdouble dividendsh. The purpose of the present paper is to examine...

All the social insurance systems in Japan have faced number of difficulties in recent years mainly because, on the one hand both aging and number of children declining had accelerated and on the other hand Japan experienced stagnated economy after 1990. Among them the public pension system...