一种新的效用理论观点下的均衡市场结构

Equilibrium Market Structure under a New Utility Theory

文中提出一种新的效用理论观点:某种水平差异产品的效用和消费者在挑选该产品时的其它可供选择的替代商品的数量成正比。换句话说:可供选择的替代商品的种类越多,商品的价格就越高。在这种情况下,工厂和商店都面临着一个取舍问题:随着可供选择替代品种类的增多,单个商品的售价可以得到提高,可是其被售出的机率又会降低。我们构建模型来研究均衡市场结构的特点。在5种市场结构中,只有"多个销售多种产品的商店"的市场结构才是稳定和均衡的市场结构。文中的模型在研究市场结构方面要比搜索模型更加真实。文章的一些假设条件较牵强,希望在以后的研究中能够放宽。

We propose a new standpoint to view the utility theory, in that the utility from a horizontally differentiated product （HDP） is positively related with the number of other HDPs available for the consumer to choose. Put in an- other way： as the number of alternative products increases, the price for one product will rise as well. Under such sit- uation, both manufactures and retailers face a tradeoff： while a product＇s price can rise as the number of alternative products increases, the chance of it being sold will decreases. We build a model to characterize the market equilibri- um under such tradeoff, of the five market structures, only ＂multi-retailer selling more than one product＂ is a stable and equilibrium structure. This provides a more realistic market structure than do searching models. We hope some of the strong assumptions can be relaxed in future studies.