由於連網技術的進步以及網際網路的普及，全球以網路銷售為主的企業正發揮其影響力，促使消費型態的轉變，現今的顧客不再侷限於前往實體店面進行採買，網站上面一鍵購買的消費方式逐漸被視為選項之一，此現象連帶讓企業開始思考加入第三方平台的銷售模式，以應付市場的趨勢，在這其中網路團購平台是一種熱門的銷售策略，消費者在特定銷售期間，只要累積一定的購買數量，即能享有產品的低價折扣，因此團購的推出能在短時間內為銷售店家創造龐大的需求，然而為了吸引不知情的消費者購買新產品，銷售店家的團購定價必須做出大折扣的犧牲，才能滿足顧客心中的購買意願，迫使銷售利潤的減少，此外在多通路的銷售之下，如何降低第三方網站瓜分原有客群的影響也是銷售方需要探究的問題。
本研究探討單一銷售店家推出新商品時的銷售策略，銷售店家有兩種銷售通路，分別為自有店鋪與第三方團購網站，在銷售店家與團購網站各自最大化利潤下，建構四種情況的通路銷售模型，透過效用函式代表異質性顧客對於產品的認知價值，並將顧客群區分為二類，分別為策略性顧客以及團購顧客，分析加入團購網站的銷售能否幫助銷售方提升利潤，最後藉由參數的分析，結果發現團購的網路外部性與自有通路價格以及團購門檻值呈正相關，但卻對批發價格呈負相關。在單一通路銷售下，團購通路銷售比起透過自有通路銷售來的有利，而雙通路的銷售比起單通路而言更能提升利潤，此外團購網站透過適當的促銷策略能提升平台的需求量，同時增加網站收益，達到雙贏的局面。

Online sales become a large share of commerce and change consumption patterns. Group buying is a popular online-sales strategy and offers products at reduced prices on the condition that a minimum quantity of products is placed. This study develops a game model, in which a single retailer who offers a single product to heterogeneous consumers in the four sales scenarios. The product is offered: (1) at the retailer’s brick and mortar stores, (2) exclusively on a third party group buying website, (3) in a dual sales channel, and (4) dual sales channel with GB website using early-bird promotion, with the aim of maximizing the profits for the retailer and third party. Consumers are classified into two segments: strategic and group buying consumers with different perceived utilities for the product. Suppose that the strategic consumer possesses a certain degree of the product information and is also willing to turn to purchase the product on a group buying website rather than at a brick and mortar store, which would enhance the network externality and attract more consumers without a sufficient understanding of the product to participate in group buying. The analysis result indicates that the profit for the dual channel strategy is better than that for the single channel strategy when the market size of GB website is relatively high. The early-bird promotion is beneficial for both parties, and the website’s network externality is the most critical factor for sellers who want to participate in group buying sales.

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