在母體為常態且變異數已知或未知的情況下，先前的研究者已透過兩階段抽樣方法來處理變異數的問題。但由於兩階段抽樣方法缺乏實用性，且必須再額外增加樣本數，因此本研究使用一階段抽樣方法及子集合選取的方法來消除變異數異質性的問題。除此之外，本文亦提供針對每組樣本大小不同下的資料進行一階段抽樣方法，並透過網頁設計的方式，提供使用者一個介面能將資料進行分析並選擇最佳t個母體。

In cases where the normal populations with the variances are unknown and unequal, previous researchers have developed Stein-type two-stage sampling procedures for normal populations under heteroscedasticity. However, due to the lack of practicality of the two-stage sampling method and must requiring additional samples, this study uses single-stage sampling method and subset selection method to deals with the unknown and unequal variance problems. In addition, this article provides a single-stage sampling method for different sample size, and provides a user interface to analyze the data and select the t best population through the web design.

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