統包工程招投標機制設計分析

統包工程承攬模式大幅地降低了工程價值鏈中諸多業者的交易成本，增進業主的投資效益，刻正興起且被廣泛應用。透過對工程專案風險的分析，本研究歸納出承商的履約能力為統包工程專案成功的關鍵因素。本研究運用賽局架構，分析統包工程最有利標與最低價標機制設計。研究發現，在有利標的評選中，對廠商的評比項目的選定應能讓廠商揭露其私人訊息，使業主能有效地區分廠商的能力型態，以排除逆向選擇的可能性。本研究以不完美訊息的招投標賽局模型取代不完全訊息的招投標賽局的模型，推導最低價標均衡報價模型並求得最佳解。結果發現，當投標廠商減少則廠商的效用最大；當投標廠商增加時，廠商的生產者剩餘為0，此時業主有充分的價格談判力。從計算結果亦發現業主的保留價格設定如同增加一個投標廠商的效果。在決標過程中，合宜的底價有助於業主降低採購的成本。本研究檢討三種型式的統包合約，即固定價格合約、成本加酬金合約與混合式合約。固定價格合約給承商降低成本最大的激勵，但也可能提高業主的成本。成本附加酬金合約的投標價格比固定價格合約低，但所有的成本風險全由招標人承擔。混合式的合約補救固定價格與成本附加酬金合約的不足，可以目標價格、保證最高價格或其他方式作為獎勵或懲罰承商的合約條款。

關鍵字

統包；招投標；賽局；委託代理；機制設計；合約

並列摘要

The emerging EPC project contracting has been widely adopted for its effective reduction of transaction cost among suppliers in the value chain of construction business. Through risk analysis, the research summarizes that the key successful factor to an EPC project is the ability of the contractor to carry out the contracts. A game model was established to analyze the mechanism design of contractor selection process. Two types of contractor selection model, the most advantageous tender and the lowest price tender, were studied. It is found that the evaluation items for the most advantageous tender should be effective to reveal private information of the tenders, so that the client can identify the type of tenders. A target function for the lowest price tender was formulated and solved for optimum solution in the study. It is found that, when the number of tender decreases, the payoff of the tender increases, while the number of tender increases, the utility of tender decreases, which implies that the client has more bargin power. The calculating results show that client’s reserved price acts like another competing tender in the pool. It is also proved that a proper reserved price setting can effectively save client’s budget. Three types of contract, fix-cost, cost-plus and hybrid, were reviewed in the study to verify its compatibility with EPC project.