中文摘要：

重复购买率的提升成为网上商店的核心竞争力，基于淘宝网实际交易数据研究价格、广告因素对重复购买的影响关系，实证检验得出：商品价格与重复购买率之间存在倒u型关系，结论符合期望失验理论：广告投入与重复购买率之间存在U型关系，体现了广告投入的规模效应递增规律．在此基础上，进一步对比分析了搜索型、体验型、信任型三种不同商品类型的敏感度差异．研究丰富了C2C环境下的消费行为理论，同时为网店运营提供必要的决策支持．

英文摘要：

Enhancing of repeat purchase rate has become the core competency of online stores. Based on the real transaction data of TAOBAO, this paper analyze the influence of price and advertisement on repeat purchase, and concludes through an empirical model： Inverted U-shaped relationship exists between commodity prices and repurchase rates, which confirm the expectancy disconfirmation theory; The root cause for the U-shaped relationship between advertising investment and repurchase rates is increasing returns to scale of advertisement. Further more, this paper also make a comparative analysis on the sensitivity of three categories commodities, that of search type, experience type and credence type. This study enrich the theory of consumer behavior in C2C environment and provide the necessary decision support for online stores.