[問題] 94清大統計(已解決)
這題在數學板有發過 沒人回答案
所以不好意思來這裡再次發問
Suppose that there are k different coupons and each time one obtains a coupon
it is equally likely to be any one of the k types.
Let X be the number of different types of coupons that are contained in a set
of n coupons.
Compute E(X) , Var(X)
題意看不太懂
第一段大概看得懂
第二段講到X是代表什麼 不太清楚
那X的p.d.f.為???
麻煩瞭解的人解答一下 感謝M(_ _)M
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05/23 02:00, , 1F
05/23 02:00, 1F
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05/23 02:00, , 2F
05/23 02:00, 2F
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05/23 14:33, , 3F
05/23 14:33, 3F
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05/25 00:06, , 4F
05/25 00:06, 4F