Internet市场遵循“一价定律”吗?——来自天猫商城的证据

Does the Internet Market Follow the Law of One Price?——An Evidence from Tmall Website

根据搜寻理论,线上市场由于极大地降低了消费者搜寻成本,应当实现"一价定律",然而大量的证据表明线上市场存在显著的价格离散现象。文章选取了中国最大B2C电子商务平台天猫商城上高度同质化、标准化的虚拟产品——手机充值卡作为研究对象,发现确实存在价格离散现象。然后,利用固定效应向量分解模型和蒙德拉克模型,检验了哪些因素会影响价格离散程度,发现零售商异质性越大、商家数量越多,价格离散程度越大;商品越是畅销、商品价值越大,其价格离散程度越小。文章在数据上有较大创新,对已有文献形成有益补充;结论有助于增进对中国线上市场效率的认识,能够为Internet市场"效率悖论"提供一些线索和启示。

According to the theory of search,the online market should hold the one-price rule since consumers＇ search cost isgreatly reduced,but a lot of evidence shows that price dispersion prevails in the online market. This paper chooses the prepaid calling card from the Tmall website,the highly homogeneous standardized virtual product,as the object of this study. The results from Kernel Density Estimation show that price dispersion does exist. Besides,by using Fixed-Effect Vector Decomposition model（ FEVD）and Mundlak model,this paper explores the factors that affect the degree of price dispersion. It is found that an increase in the retailer heterogeneity and the number of retailers may aggravate price dispersion while an increase in the popularity and the value of goods may reduce price dispersion. In addition,the degree of price dispersion exhibits downward trend over time. This paper constitutes a useful supplement to the existing literature due to the innovative data analysis. The conclusions contribute to understanding the efficiency of the Chinese online market and provide some clues to the Internet market issue of ＂efficiency paradox＂.