在軟體系統開發的過程中，如何決定需求的可行性對於日後的系統功能與開發成本具有關鍵性的影響。需求的取捨與優先順序往往涉及許多複雜的因素，也是軟體工程相關領域的研究重點。本研究的目的在於發展一個軟體需求的決策模式，提供系統開發組織與人員以及使用者對於各項需求進行量化的評估，以符合預期的目標，增進系統的資訊品質，提升軟體流程改善效益。在研究方法上首先以建立階層式模型的方式，將影響軟體系統需求的各個特徵項目歸納至適當的需求類型屬性中。接著模擬專家對於各項目的評估資料，再利用主成份分析法(Principal Component Analysis)計算最大特徵值與特徵向量，決定系統需求的優先順位。最後並以交互驗證分析方式檢驗研究方法的?定性。本研究的結果嘗試建立一個模擬專家對軟體需求順位的評分模式，同時可將這些需求項目列入系統分析階段的需求規格書，做為開發與驗收的基準，未來可以結合軟體品質度量的觀念做為協助軟體流程改善的參考。 During the process of software development, the feasibility study in the determination of software requirements plays a primary role in system functionality and developing cost. The prioritization of various requirements affected by many complicated factors becomes one of emphasized research topics. The goal of this research is to establish a decision model for prioritization of software requirements. This model can be used as a quantitative evaluation method of requirements by developing staff and general users. The resulting information system should match the expectation, improve information quality and promote software development process effectively. Our research start with a hierarchical model for representing important attributes of interest and grouping them into some categories. Next, we generate values of these attributes randomly and apply the Principal Component Analysis to calculate the maximum eigenvalues of covariance matrix of attributes, its corresponding eigenvectors and the priority of each software requirements. Finally, we conclude the model stability by a cross validation study. The result of this research might be an aid to developers in software requirement planning stage objectively. Also, the attributes discovered in analysis stage can be included in the software requirements documents as a baseline in developing stage and project completing stage. Furthermore, combing with the concept of software measurement, our result can be an important reference in software process improvement.
