要旨：Models of club good, local public good, and growth control appear to have theoretical structures distinct from usual oligopoly models. This article shows however that they are special cases of a generalized oligopoly model that incorporates the possibility of two-part pricing and externalities between consumers (either congestion or network externalities). Our generalized two-part pricing model not only serves as a synthesis of a wide range of models but also allows us to obtain several new results on equilibrium prices. Another advantage of our model is that it can be considered as a reduced form of more complicated models that have spatial structures. This allows us to easily generalize the analysis to the case where firms are heterogeneous and the number of firms is arbitrary.

要旨：The purpose of this paper is to analyze Nash tax competition among governments that differ in geographical aspects such as their sizes and positions. Each government lying on a linear market maximizes its revenue with respect to its own commodity tax rate, taking into account the cross-border shoppings induced by the difference in tax rates. In particular, we examine how the size of the countries and their spatial arrangement affect tax rates and government revenues at a Nash equilibrium. We show that a small country chooses a lower tax rate than a big country, and obtains more than its size-proportional share of total revenue at the Nash equilibrium. We also prove that when the size of all countries are identical, the tax rates levied by the governments go down from either market boundary toward the market center, and the adjoining countries of peripheral countries can obtain the larges government revenue.