本文主要目的為探討軟體廠商遏止盜版成本提高與盜版相對正版的品質提高會如何影響軟體廠商遏止盜版的資源投入多寡，並進一步分析對軟體產品的品質、價格、消費者對正版與盜版軟體的使用量、軟體廠商利潤、消費者剩餘，以及社會福利的影響。主要結果指出，當遏止盜版成本提高，軟體廠商會降低遏止盜版的資源投入，但是會提高產品品質，且降低產品價格。同時，消費者對正版的使用量會下降，但對軟體的總使用量會上升，廠商利潤減少，消費者剩餘上升，社會福利會上升。然而，當盜版相對正版的品質提高時，因盜版產品品質相對於正版差異較小，軟體廠商會增加遏止盜版的資源投入，且降低其正版產品品質。此外，雖消費者對正版的使用量會上升，但是對軟體的總使用量會下降，廠商利潤減少，消費者剩餘下降，社會福利會下降。

This paper aims to examine how a software firm responds to the rising costs of anti-piracy, and to the case when the quality of a pirated version increases to approach that of a genuine version. The main result shows that, as the firm’s costs for anti-piracy increase, the software firm lowers its investment in anti-piracy while it raises product quality and lowers price. In addition, the demand for the genuine version and the profits of the software firm both decrease, but the total consumption of the software (including both of genuine and pirated versions), consumer surplus, and social welfare all increase. As the quality of a piracy version (relative to that of a genuine version) increases, because the quality differentiation between genuine and pirated version is reduced, the software firm raises anti-piracy investment while it lowers products quality. In addition, although the consumption of genuine version increases, the total consumption of the software, profits of firm, consumer surplus, and social welfare all decrease.

審定書 i
誌謝 ii
中文摘要 iii
英文摘要 iv
目錄 v
第一章 前言 1
第二章 文獻回顧 4
第三章 基本模型 6
第四章 均衡分析 8
第五章 結論 15
參考文獻 17
附錄 18
附錄1：【命題一】證明 18
附錄2：【命題二】證明 18
附錄3：【命題三】證明 19
附錄4：【命題四】證明 20
附錄5：【命題五】證明 20
附錄6：【命題六】證明 20
附錄7：【命題七】證明 21

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