基于交易服务的第三方B2B电子商务平台模型

Model of third party B2B e-commerce platforms based on transaction services

以现货交易模式为背景,运用微观经济理论和网络经济理论,对一个第三方垄断B2B电子商务平台进行形式化建模。证明了交易服务存在内生的双边网络效应:卖方(买方)从服务中获得的价值随买方(卖方)数增加而增加但随卖方(买方)数增加而减少。结合效用函数和利润函数,推导出卖方(买方)的最优服务价格等于第三方的边际成本加上买方(卖方)的边际成本与边际协同收益的差额。分析了商品供需特征等参数对平台利润的影响,结果显示:为获得更多的利润,第三方应将交易服务定位于供给和需求对价格敏感、市场供需量大的大众化商品和大宗商品,同时采取有效措施降低买卖双方的平台使用成本。

This paper presents a formal model of monopoly business-to-business （B2B） e-commerce platforms owned by a third party in spot trading modes using microeconomics and network economics. Endogenous two-sided network effects were proved in transaction services that the value of services to suppliers （buyers） increases with increasing number of buyers （suppliers） while decreases with increasing number of suppliers （buyers）. Combination of the utility functions with the profit function deduced that the optimal service price to suppliers （buyers） is equal to the marginal cost of the third party plus the difference between the marginal cost and the marginal collaborative income of buyers （suppliers）. Analyses of the impact of such parameters as characteristics of commodity supply and demand on the platform benefit show that for more benefits,the platform owner must aim at transaction services of staple commodities with high price elasticity and large quantities of market supply and demand,while reducing the marginal usage costs of buyers and suppliers with effective measures.