產品可靠度 (reliability) 是決定消費者挑選產品之重要影響因素，因此如何從眾多供應商中，建構適當的擇優挑選法則 (selection rule) 來挑選出具有能生產高可靠度產品能力之最佳供應商是生產者經常面臨之重要決策問題。 本研究在假設供應商之產品衰變路徑服從逆高斯衰變模型，探討如何建構適當之擇優法則及規畫衰變試驗之最適實驗配置 (包括測試樣本、觀測頻率及終止時間) 之決定。 具體而言，在確保可正確挑選出最佳供應商之機率達到給定的 P^* 及做錯誤決策機率要小於 α^* 下，決定可使得實驗總成本極小化之最適配置。 最後並舉例說明如何使用本文所建構之挑選法則；與傳統的挑選法則相比較，可發現本研究所建構的挑選法則之最大優點是可以有效地降低實驗所需的樣本數及總實驗時間。

At the research and development (R & D) stage, the manufacturers may wish to select the most reliable product (supplier) from among several competing products (suppliers). In this study, assuming the degradation paths of product’s quality characteristics come from an inverse Gaussian degradation process, we first apply locally optimal (LO) criterion to construct a suitable selection rule. Furthermore, with a minimum guarantee of probability of correct selection (CS) of the proposed rule, we deal with the optimal design of a degradation experiment (which includes the determinations of the sample size, sampling frequency and the termination time) in such a way that the total experimental cost can be minimized. Finally, we use an example to demonstrate the proposed procedure. From the results, it shows that our proposed procedure has the ability of substantially reducing the sample size and termination time, which are needed to conduct a degradation experiment.

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