吾人日常生活中常遭遇類似囚犯兩難的問題，如返還遺失物、幫助陌生人、遵守規則，以及慈善捐贈等。傳統囚犯兩難賽局下的Nash均衡是雙方皆不合作，然而日常生活中實不乏合作的例子存在，因此有必要對PD賽局加以研究。

本文利用演化方法，加入C類型與D類型於Guttman(1996)的模型中分析，試圖探討囚犯兩難賽局之合作行為變化。本文除了使Guttman的模型更為一般化之外，將使傳統文獻發展更為完整。

本模型在單方不確定下存在兩種人，甲（R）是理性人，乙（MR）試可能理性人。甲懷疑乙可能是理性人、機械式TFT、C或D類型。研究結果發現：在混合策略的PBE中，對任何參賽的階段小於preempt前一階段而言，R不會採行非合作策略；對任何參賽的階段小於preempt前兩階段而言，MR不會採行非合作策略。當雙方交手次數增加時，非合作階段數維持不變，亦即，合作階段數隨交手機會增加而提高。最後透過比較靜態分析得知，當甲認為乙是C類型的可能性增加時，他可能提前或延後preempt策略以探索乙的類型。若甲認定乙是TFT類型的機率較小，使得preempt的策略報償大於和乙同時由C轉變為D的策略報償時，他會提前preempt以剝削乙。而當甲認定乙是TFT類型的主觀機率增加時，他會延後preempt以避免遭受乙的懲罰，故此時合作的機會增加。

單方不確定性的結果可以一般化至雙方不確定的情況。

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