本文討論官員以企業要進入市場必須購買營業執照為由，向企業收取所需的費用，在兩階段的模型中，官員可以對不同類型的企業差別取價，並且承諾其要求的費用，我們獲得官員最適的要求費用以及企業進入市場的條件。當考慮影子經濟時，本文證明影子經濟的存在會對官員產生抑制作用。從官員的最適收費和最適企業進入條件這兩方面進行分析，本文發現在有影子經濟下官員的收益會減少。

This article discusses the corrupt official and entrepreneurs. When entrepreneurs want to operate in the market, they have to purchase license from the official. In two-stage model, the official can take different prices of different types of entrepreneurs, and commits to his demand. We get the optimal demands of the official and critical types of entrepreneurs. In the framework with the shadow economy, the official is forced to decrease his demands. By examining the optimal demands and critical types, we found that the official’s benefits decrease in the shadow economy.

目錄
論文審定書....................................................................i
誌謝................................................................................ii
中文摘要........................................................................iii
英文摘要........................................................................iv
第一章 緒論..................................................................1
第一節 研究動機與目的..............................................1
第二節 本文架構..........................................................3
第二章 文獻回顧..........................................................4
第三章 理論模型..........................................................7
第一節 模型假設..........................................................7
第二節 影子經濟下兩階段模型..................................17
第三節 分析討論...........................................................27
第四節 影子經濟下的最適收費...................................31
第四章 結論與建議.......................................................35
第一節 研究結論...........................................................35
第二節 未來研究方向與建議........................................36
參考文獻..........................................................................37
圖目錄
圖一 企業數量累積分配................................................11
圖二 企業兩階段進入市場選擇....................................17
圖三 企業兩階段選擇官方經濟.....................................20
圖四 企業兩階段選擇影子經濟.....................................21

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