本文探討了平台採取搭售策略的誘因及其對訂閱戶、廣告商的定價、人數和福利的影響，並分析了搭售可能導致的市場封殺效果。平台(廠商1)除了在市場A提供平台服務，還有在市場B販售一般性產品。當平台未搭售時，廣告厭惡程度下降會使平台對訂閱者收費先降後升，對廣告商收費下降，廣告數量上升，而被搭售的市場B自家產品價格和數量不變。當消費者對產品忠誠度低時，搭售必會導致市場封殺，使廠商2退出市場；忠誠度中等時，當廣告厭惡程度低時搭售會導致市場封殺，厭惡程度高時則不會；忠誠度高時，搭售則不會導致市場封殺。若搭售未導致市場封殺時，廣告厭惡程度下降使平台的組合價格先降後升，廣告數量上升，而市場B中B1產品數量先降後升，對手產品數量則先升後降。此外，比較搭售前後，我們發現搭售會使平台使用人數下降，廣告價格下降但數量不變，B1銷量增加，B2價格和銷量減少。兩廠商總收入降低，訂閱者和廣告商剩餘增加，社會福利下降。但若搭售造成市場封殺，平台收入增加，社會福利減少。此外，我們的結果發現只有在平台的搭售策略會導致市場封殺下，平台才有誘因進行搭售。

This paper examines the incentives for a platform to adopt bundling strategies and their effects on pricing, user numbers, and welfare for subscribers and advertisers, along with the potential for market foreclosure. In addition to providing platform services in market A, platform (Firm 1) also sells general products in market B. When the platform does not bundle, a decrease in ad aversion initially lowers subscriber fees, then raises them, decreases advertiser fees, and increases the number of ads, while prices and quantities in market B remain unchanged. In additional, we find that with low consumer loyalty, bundling leads to market foreclosure, causing firm 2 to exit. With medium loyalty, bundling results in foreclosure if ad aversion is low, but not if it is high.
With high consumer loyalty, bundling never leads to market foreclosure. Furthermore, when bundling does not cause foreclosure, decreased ad aversion initially lowers then raises the bundle price, increases ad numbers, and also affects market B's prices and quantities. Bundling reduces platform users, lowers ad prices while keeping ad numbers constant, increases B1 sales, and decreases both the price and sales of B2. Both firms' total revenues decrease, while subscriber and advertiser surplus increases, reducing social welfare. If market foreclosure occurs, the platform's revenue increases, but social welfare decreases. Lastly, we show that the platform is incentivized to adopt bundling only when it leads to market foreclosure.

目錄

論文審定書i
摘要ii
Abstractiii
目錄iv
圖次v
第一章前言1
第二章文章回顧4
第三章模型設定6
3.1未搭售7
3.2搭售下未出現市場封殺10
3.3搭售下出現市場封殺16
第四章結論21
參考文獻22
附錄一27
附錄二29

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