企业的最优产品差异化选择

The Optimal Product Position Choice

本文考察了环形城市模型中交通成本对企业最优产品差异程度的影响。企业首先选择产品差异程度，然后进行价格竞争。我们发现：与人们通常的认识——交通成本的凹凸性决定了企业产品差异化倾向——不同；边际交通成本的凹凸性起了关键的作用。当边际交通成本的倒数为凸函数时，企业将选择最大的产品差异化程度。本文指出，产品差异最大化能够得到社会福利最大化，但市场竞争不一定能得到这个结果，此时资源配置的效率存在改进的空间。

This paper explores how the cost function of transportation affects the optimal product position. In the game, firms choose their product positions first. Then they engage in price competition. We find that, it is the concavity of the inverse of the first derivative of the transportation cost function that guarantees the equi-distance positioning in equilibrium. When the inverse is concave, firms choose maximum product differentiation, which is Pareto optimal. However, free market competition does not always yield such desirable outcomes, in which case potential Pareto improvements are possible.