中文摘要：

为找到电子商务企业高投入、低投资回报现象存在的原因,本文首先运用数据包络分析（DEA）模型计算了电子商务企业投入对产出的过度效应,即投入拥挤,然后将之与行业内的市场竞争程度和移动电子商务的发展相结合,通过构建面板数据回归模型,详细探讨了动态市场竞争环境下电子商务企业盈利能力的影响因素。研究结果证实了资产规模过大对传统电子商务企业盈利能力具有削弱作用,而市场集中度和移动电子商务的发展则对传统电子商务企业盈利能力具有推动作用。这些发现启示企业经营管理者应聚焦于移动电子商务发展带来的新机遇,消除投入拥挤,通过调适生产规模和新业务模式的创新,开辟新的营销渠道和盈利模式。

英文摘要：

A major current focus in e-commerce study is to explore why there are high inputs but low profits in e-commerce.Focusing on the excessive effect of inputs on outputs,market competition rate and mobile e-commerce development,input congestion amount is firstly calculated using data envelopment analysis models,and then e-commerce firm profitability determinants are explored by constructing the panel data regression model.Thirty five pure e-commerce websites from the stock markets of Shanghai,Shenzhen,Hong Kong and NASDAQ are considered,all of which utilize at least one of the two e-business models,namely business-to-business（B2B）and business-to-customer（B2C）.The results of DEA models identify that e-commerce suffers from congestion,and the regression shows that asset input congestion has a negative effect on e-commerce firm profitability while market concentration rate and the development of mobile e-commerce can strengthen e-commerce firm profitability.These findings indicate that it is input congestion that leads to low profits.It also enlightens decision makers to strengthen their profitability by eliminating congestion resources and adding new marketing channels such as mobile e-commerce.