政府採購法的決標方式原本分為最低標及最有利標兩種，行政院工程會(簡稱工程會)於95年函頒「機關異質採購最低標作業須知」規定，並於99年增訂異質採購最低標決標方式(簡稱異質最低標)，使得採購法決標方式增加到三種。然採購法對於各決標方式之選擇時機與條件，卻未提供客觀之決策標準。機關採購人員為免圖利廠商，多傾向選擇作業單純的最低標方式，使得最有利標或異質最低標之立法美意無法有效發揮。先前研究已提出以效能彈性為理論基礎之「價格效能分析模式(P/PAM)」，作為判斷最有利標及最低標決標選擇之依據，但尚無法涵蓋異質性介於同質與異質間之異質最低標。為彌補此一弱點，本文以P/PAM圖形為基礎架構，建構一種新的異質採購圖形分析模式(簡稱P/PAM-GAM)。此方法可以簡易之圖形判讀，分析產品之異質性，進而決定適當的決標方式，以分析採購法所規定的三種決標方式之適用條件。最後，本文以二個採購案例為個案研究，以說明P/PAM-GAM實用性，並與P/PAM分析及比較。

There are two major contractor selection methods, the Lowest Tender (LT) and the Best Value (BV) as defined in the Government Procurement Act (GPA). The third contractor selection method, namely the Heterogeneous Lowest Tender (HLT) was proposed by the Public Procurement Commission (PPC) in 2006 and was later formally defined in GPA in 2010. However, there is no quantitative method provided by the GPA to support the selection of the most appropriate one from the three methods. The procurement staff of government agencies tends to choose LT in order not to violate the regulations. As a result, the government procurement could not benefit from the merits of BV and HLT. Previous research has proposed a Price/Performance Analysis Model (P/PAM) to assist the selection decision from the LT and BV, but the P/PAM method does not cover the HLT method. To improve on this drawback, the current paper presents a new graphical model for analysis of heterogeneous procurement, namely P/PAM-Graphic Analysis Model (P/PAM-GAM). The proposed P/PAM-GAM provides an operational method based on a simple graphical analysis of figures generated in P/PAM so that appropriate decisions can be made for the three types of contractor selection scenarios defined by the GPA. Finally, two practical procurement examples, including product procurement and a design/build (D/B) construction project, are demonstrated with the proposed P/PAM to illustrate the applicability of the proposed model. Practical issues related to the adoption of P/PAM are also addressed.