如何比較並選出較高製程能力的供應商，一直是供應商選擇中會面臨到的問題，本研究應用Wang [14] 所提出的製程良率指標S_pkA，來比較當兩供應商製程資料呈線性剖面資料時，何者有較高的製程良率，本研究利用假設檢定方法來檢測兩供應商的優劣，並利用需要的剖面資料個數控制檢定力，在最後也提供了一印刷電路板的實際案例分析以供參考。

Comparing two suppliers and selecting the one that has a higher process capability is an important selection problem. This study proposes the ratio test statistic based on the process yield index S_pkA proposed by Wang [14] for two-supplier comparison for linear profiles. Testing hypotheses for comparing two suppliers are developed in this study. The number of profiles required is established at a given power and significant level. In study, the real data from a printed circuit board process is used to demonstrate the application of the proposed method.

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