道德風險起因於資訊不對稱以及委託人和代理人目標的不一致，此外，公 平性考量也是造成訂約雙方的目標不一致的一種內在因素。本文在隱藏性行爲 存在的前提下，將公平效用導入傳統的契約理論模型，分別探討「最適效率工 資」與「最適誘因工資」的決定與公平效用的關係。本文研究結果指出，因爲 兩模型的誘因機制不同——委託人在效率工資中使用不續聘「懲罰」，而在誘 因工資中使用產出分成「獎勵」，造成面對公平性考量之衝擊時的「最適反應」 相異。在公平考量程度不高時，兩契約下的最適工資隨公平要求程度而上升； 效率工資契約的最適心力付出隨之上升且代理人效用上升，而誘因契約的最適 心力付出隨之下降而代理人效用不變。不過隨著公平考量程度的更加提高，到 超過一定界限時，兩契約皆停止交易。

Moral hazard is caused by information asymmetry and the inconsistency of principal’s and agent’s objection. Besides, fairness concern could be also an internal factor that contributes to the inconsistency within the contract. (Fehr et al., 2007) In the context of hidden information, this thesis incorporates fairness utility into the traditional contract theory models and discusses the impact of fairness concern in the “optimal efficiency wage” and “optimal incentive wage.” Because the mechanism of incentive dealing is different, the principal could stop hiring the agent as punishment in the efficient wage contract while uses output sharing to reward the agent in the incentive contract, the impact of fairness concern on two contracts is different. When the fairness concern is tiny, the optimal wages under both contracts increase. The optimal effort and agent’s utility increase under the efficiency wage contract, while the optimal effort decreases and the agent’s utility remains under the incentive contract. However, when the fairness concern is massive, the transaction in both contracts could terminate.

論文審定書 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . i
誌謝. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ii
摘要. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . iii
Abstract . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . iv
第1章 緒論 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
1.1 研究動機 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
1.2 本文模型設定的基本要素 . . . . . . . . . . . . . . . . . . . . . . . . . . 5
第2章 效率工資契約. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
2.1 考慮公平性效用的效率工資模型 . . . . . . . . . . . . . . . . . . . . . . . 8
2.2 最適心力投入與最適效率工資 . . . . . . . . . . . . . . . . . . . . . . . . 10
2.3 針對不同形態代理人的靜態均衡之比較 . . . . . . . . . . . . . . . . . . . 13
第3章 誘因工資契約. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
3.1 考慮公平性效用的誘因工資模型 . . . . . . . . . . . . . . . . . . . . . . . 18
3.2 最適心力投入與最適誘因工資 . . . . . . . . . . . . . . . . . . . . . . . . 20
3.3 針對不同形態代理人的靜態均衡之比較 . . . . . . . . . . . . . . . . . . . 23
第4章 結論 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
參考文獻 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

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