自從網際網路商業化以來，B2C電子商務的蓬勃發展提供了異於傳統的銷售通路，藉由網路世界所帶來的方便性，創造了許多消費者在網際網路購物的習慣。許多電子商務之相關研究在量的方面也有長足的進展，然而過去B2C電子商務的文獻著重於探討購買意願以及消費者行為，雖然不少文獻提到了顧客保留的重要性，甚至有少數文獻嘗試找出影響顧客忠誠度的因素。然而不論顧客忠誠度之定義為何，現有的文獻大都以調查網購者對店家之觀感、或網購者自己所回答的再購意願為依歸，而不曾以真實的網站交易資料為依據，定義並評估顧客忠誠度的指標。 不論是B2C電子商務實務經營者，或是研究者，儘管重視顧客保留，卻無法對顧客保留的衡量有所突破，或形成一個比較的基準，以檢視顧客保留的現狀與變化。有鑑於此，且因顧客保留與顧客流失為一體的兩面，本研究計畫擬賦於顧客流失和顧客保留量化的定義，提出一個根據顧客資料和交易資料建立衡量基準、評估顧客流失和顧客保留之模式。本計畫認為顧客流失或顧客保留並非是一個數字，而是一種隨時間移動的衡量，本計畫將與台灣地區之B2C電子商務網站進行合作，取得顧客資料以及交易資料，根據所提出之模式，評估、分析、解釋在B2C電子商務網站經營之意涵。 Since the commercialization of the Internet, the rapid growth of e-commerce has offered a distinctive sales channel that is in many ways different from traditional ones. The convenience created by the online world shaped many consumers’ habit to shop online. In the past decade, numerous studies have contributed to the understanding of e-commerce consumer behavior and e-commerce purchase intention. A few studies mentioned the importance of customer retention, and some attempted to identify the factors that affect customer loyalty. Yet, no matter what the definition of customer loyalty is, most of the extant literature approached the issue by either measuring online shoppers’ perception toward e-commerce websites or asking shoppers to express the degree of repurchase intention. Few studies defined and evaluated customer retention or customer attrition based on the actual transaction data. Both practitioners and researchers embrace the concept of customer retention. But in order to assess customer retention, a breakthrough in the quantification aspect is necessary. In light of this, this project will give customer attrition and customer retention quantifiable definitions and propose a model to assess them based on customer information and transaction data. It is the stance of this project that customer attrition is not a number, rather it is a multi-facet measurement. This project will collaborate with B2C e-commerce companies in Taiwan to secure customer information and transaction data, establish the baseline and assess the customer attrition and customer retention according to the proposed assessment model, and interpret the possible implications in the operation of B2C e-commerce business.