許多實證文獻證實，以團體借款形式在開發中國家提供小額借款，能確保企業家在無抵押品的情形下，也會依約定進行還款。因此本文憑藉Laffont (2003)之模型設定，進一步探討賽局行動順序變動，對企業家間配對時類型間相關性，以及貸方防止企業家勾結所設之限制，在不同借款契約中所造成之影響進行分析。結果發現，無論企業家在簽約前，是否能預先知道契約的運行機制，也無法從分享訊息中受益。換句話說，即使企業家是賽局中的先行者，也不代表一定能擁有先動優勢。

Many empirical papers proved that microfinance in the form of group lending in developing countries can ensure entrepreneurs’ repayment by contracts without collateral. The disertation discusses the impacts of rearranging some steps of the game in Laffont (2003) on the sustainable range of correlation between entrepreneurs’ types for lending contracts and collusion-proof constraints. It is found that entrepreneurs will not be benefited from sharing their information before signing contracts no matter whether they know the mechanisms of contracts in advance or not. That is, even when entrepreneurs are first-movers in this game, they could lose rents they would obtain without being first-movers.

論文審定書...............................................................................................................................i
摘要...........................................................................................................................................ii
Abstract....................................................................................................................................iii
目錄..........................................................................................................................................iv
圖次...........................................................................................................................................v
第一章 研究動機....................................................................................................................1
第二章 文獻回顧....................................................................................................................4
第三章 模型假設....................................................................................................................6
第一節 最適契約.......................................................................................................7
第二節 團體借款契約.............................................................................................10
第三節 在完整訊息下的勾結情形........................................................................12
第四章 不同行動順序下對契約的影響............................................................................15
第一節 簽約前可交換訊息但簽約後勾結...........................................................15
第二節 簽約前可交換訊息且可勾結...................................................................19
第五章 結論...........................................................................................................................21
參考文獻. ...............................................................................................................................23

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