網際網路興起後，結合網際網路的多通路行銷趨勢，已經非常明顯，但是許多廠商無法確定網際網路是否會增加整體的銷售量，或者只是發生掠奪的情形－即原本在實體通路購物的顧客被吸引到網際網路上，但整體的銷售量並沒有增加。本研究發展出通路間掠奪程度的經濟模型，並以資訊商品(information good)中的雜誌為探討對象，衡量線上雜誌對原本實體雜誌市場佔有率的掠奪程度，並探討哪些因素會造成網際網路掠奪實體通路。本研究使用離散選擇實驗法，造成網際網路掠奪實體通路的因素則分為雜誌選擇因素、通路選擇因素、以及個人特性。經由前測選定三本商管雜誌：商業週刊、天下雜誌及數位時代，考慮到受測者對受測產品的瞭解程度，受測者選擇某國立大學資管系與全管系的碩士在職專班及博士班學生，共有97份有效樣本（回應率為94.2%）。研究結果顯示線上雜誌會掠奪實體雜誌約30%~35%的銷售，但分析發現總體銷售量並沒有顯著的變化。研究發現線上雜誌折扣與內容試閱會影響通路間的銷售掠奪。研究也證明雜誌內容試閱程度與消費者的購買效用之間呈現倒U曲線的關係。雜誌業者應在沈沒成本的增加（網際網路商店的建置成本）與變動成本（印製、包裝及遞送等成本）的減少間，獲取30%~35%通路銷售轉移的利潤。此外多通路雜誌業者可以使用差異化定價(price discrimination)的方式，依照不同市場定位的消費者給予不同的價格，來增加利潤。

Research in the literature on electronic commerce has focused largely on analyzing their efficiency and consumer welfare-enhancing properties. But few research addressed the cannibalization issues facing the multi-channel retailers and the traditional retailers that attempt to extend their business to the Internet environment. Although the anticipated degree of cannibalization is obviously very important in determining the Internet channel extension strategy, as yet there is little empirical work that attempts to quantify it. In this paper, we develop an economic model to analyze the impact of the coexistence of Internet channel with conventional retail channel on off-line sales. Within a nested multinomial logit modeling framework, our model incorporates consumer characteristics (price sensitivity, information sensitivity, and demographices), retail characteristics (brand reputation, brand loyalty, and content), and channel characteristics (price differentiation and free trial). The proposed model is estimated and validated on individual data rather than on aggregate market data, allowing for individual heterogeneity. In addition, we also propose the method to measure the cannibalization extent and explore the strategies that retailers can pursue to segment consumers and to avoid cannibalization. A simulated shopping experiment and survey administered in a classroom setting are carried out to empirically validate the models and test the propositions. The study focuses on the Magazine industry. The findings indicate the cannibalization of 30%~35% across the electronic and the traditional channels. The resulats show that the invert-U relationship exisits between the free trial and utility. Implications for practioners are provided.