本文將網路外部性納入垂直產品差異化模型中，考慮產品品質提升的成本為凸性，進一步探討高低品質之廠商品質選擇與相容性決策。研究結果為，產品不相容時，隨著網路外部性強度增加，高品質廠商之品質先降後升、低品質廠商品質下降，品質差異程度增加，兩廠商價格與品質呈現相同的走勢，而高品質廠商市場規模增加，低品質廠商市場規模先增加後減少。而產品相容時，隨著網路外部性強度增加，高品質廠商及低品質廠商之產品品質皆增加，品質差異程度增加，兩廠商之價格與市場規模也都呈現增加。廠商均衡相容性決策: 在網路外部性強度大時，高品質廠商偏好不相容，兩產品不會相容; 在網路外部性強度小時，兩廠商都偏好產品相容，因此兩產品會相容。

This paper incorporates network externalities into a model of vertical product differentiation, where the costs of quality improvement are convex. We examine quality choices and compatibility decisions of the high- and low-quality firms. The results show that, in response to an increase in the extent of network externalities, if two products are incompatible, the quality of the high-quality good first falls and then rises, whereas that of the low-quality good falls; moreover, quality differentiation between them increases. Nevertheless, if two products are compatible, the qualities of the high- and low-quality products both increase and quality differentiation between them increases. Furthermore, we find that the two products are incompatible in equilibrium for a large extent of network externalities; however, the two products are compatible in equilibrium for a small extent.

目錄
論文審定書 i
摘要 ii
Abstract iii
目錄 iv
圖目錄 v
第一章 前言 1
第二章 文獻回顧 4
第三章 模型設定 6
3.1產品不相容 7
3.2產品相容 10
第四章 結論 17
附錄 21
英文參考文獻 23

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