作者smallpudding ( )
看板Statistics
標題[問題] 交大統研95機率論
時間Fri Mar 9 00:06:05 2007
※ [本文轉錄自 Grad-ProbAsk 看板]
作者: smallpudding ( ) 看板: Grad-ProbAsk
標題: [問題] 交大統研95機率論
時間: Fri Mar 9 00:05:01 2007
第二題:
Suppose {1,2,3,...,1000} is the finite population.
A sample of size 10 is drawn :
(a)if the sample is drawn
with replacement, what is the probability that
all 10 sample values are grater than 200 ?
(b)if the sample is drawn
without replacement, what is the probability that
all 10 sample values are grater than 200 ?
答案是(a)(8/10)^10
(b) 800
( )
10
-------
1000
( )
10
我不懂為什麼答案是這樣....
()
謝謝~
--
※ 發信站: 批踢踢實業坊(ptt.cc)
◆ From: 58.99.37.117
--
※ 發信站: 批踢踢實業坊(ptt.cc)
◆ From: 58.99.37.117
1F:推 logoer:with replacement == 取後放回...看成二項分布 03/09 10:08
2F:→ logoer:without replacement == 取後不放回...看成超幾何分布 03/09 10:11
※ 編輯: smallpudding 來自: 59.125.37.194 (03/09 10:29)
3F:推 smallpudding:我不是要問黃色字..歹勢誤導大家了 ^^|| 03/09 10:29
4F:→ smallpudding:我了解了...原來是題目看錯了>"< 英文太差Orz 03/09 10:35
5F:→ smallpudding:非常謝謝 03/09 10:36