Abstract
In this paper, the social effects of the institution that the local government pays to improve the public transport are analyzed. At first, the social benefit of various fare levels is measured using the generalized cost. Next, comparing it with the cost to improve, the social efficiency is examined. Then the tax system is constructed. And the amount of payment by local government is estimated. That is, it becomes clear how much the resident or companies in the local government must pay. In conclusion, the profitability and efficiency may become better and this system may become the basis to introduce this institute.