多階層規劃(Multi-level Programming；MLP)為多位決策者之間的目標具有階層關係之決策問題，故決策結果須遵守階層架構。首先，本研究採用模糊理論中歸屬函數的概念，將各階層的目標函數值轉換為介於[0,1]之間的目標達成度表達，藉此統一各階層目標的單位尺度。而後，本研究提出一項指標來表達決策者的權力，並以高階層決策者權力大於低階層決策者作為求解模型的限制式，用以確保決策結果符合階層關係。過往研究常假設一個階層的目標達成度即為該階層決策者之權力，因而限制高階層的目標達成度必須完全大於低階層的目標達成度。然而，當高階層的目標較難達成而造成其目標達成度較低時，此項限制將會限縮低階層的目標達成度，最終造成所有階層的目標達成度皆低的決策結果，而形成決策上的僵局。
本研究採用相加權重型模糊目標規劃求解MLP問題，且為了能夠減少僵局的發生，故在定義各階層決策者的權力時，便會考量各階層的目標達成困難度，並以一個階層的目標達成度加上其達成困難度表達該階層決策者之權力，藉此化解因為高階層的目標較難達成所形成的僵局，進而提升各階層的整體目標達成度。此外，為了使各階層決策者對於決策結果能具有共識，本研究客觀地設定各階層目標的可接受最低達成度，並假設當所有階層的目標達成度皆大於其可接受的最低達成度時，即視為各階層決策者對此結果具有共識，而不需要再調整決策，藉此提升決策的效率。
最後，本研究透過一個數值案例的演算，證明所提出之決策模型的可行性，並與過往文獻的決策結果進行比較和分析，從中發現本研究所提出之方法能得到更高的整體目標達成度，且本研究所提供之可接受最低達成度的設定方法，亦使決策模型不再發生無解的情況，而讓各階層的決策者們能更容易地達成共識。

Multi-level programming (MLP) is an approach that can be used to solve decision problems with hierarchical structures. This study proposed an indicator to represent the power of decision-makers (DMs) and used it to establish hierarchical relations. If the power of the DM is represented by the achievement degree of the DM’s goal, a constraint should be provided in which the achievement degree of the higher-level DM’s goal must be greater than that of the lower-level DM’s goal. When the higher-level DM’s goal is difficult to achieve, resulting in low achievement degree of the goal, it will make the achievement degree of the lower-level DM’s goal small. Such a deadlock will result in the low achievement degrees of all goals at each level.
To enhance the achievement degrees of overall goals, the difficulty degree to achieve goals at each level will be considered in this study when measuring the DM’s power. The DM’s power will be represented by considering both the achievement degree and the difficulty degree of the DM’s goal. In order to let DMs at all levels to reach a consensus on the decision-making results, this study proposed a method that objectively sets the acceptable minimum achievement degree of the goal of each level DM and requires that the achievement degree of each level DM’s goal must be greater than its acceptable minimum achievement degree so that DMs at all levels will have a consensus on the determined results. Based on the above ideas, this study established a fuzzy goal programming model to solve MLP problem. Comparisons of the proposed method and the existing fuzzy goal programming approaches in solving MLP problem, it showed that the proposed method can obtain higher achievement degree of overall goals.

蔡昭廷. (2015). 以模糊目標規劃求解多階層單目標之決策問題. 成功大學工業與資訊管理學系學位論文, 1-68

林芳儀 (2017). 以模糊目標規劃法求解多階層決策問題. 成功大學工業與資訊管理學系學位論文, 1-68

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