本文第二章介紹了四個版本的秘書問題，並且在第三章作變化，研究新型的秘書問題。
在原始版本的秘書問題情境下，增設了錄取門檻－及格分數的限制，未達及格分數者，不予以錄取。已知不及格人數共有𝑡位，我們目標是最大化選中實際第一名的機率。

In Chapter 2, we introduce four versions of the secretary problem, and make its new variation in Chapter 3.

We add the “threshold value” (or “passing score”) into the situation of the standard secretary problem, and the one whose scores are below this value would not be admitted. Given t, the total number of people who fail, we hope to find the maximum probability of selecting the best person.

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