作者protwister (事人物)
看板Statistics
标题Re: [问题] 有关机率的问题..
时间Fri Dec 5 09:27:36 2008
※ 引述《bluesnow4425 (衰弱残)》之铭言：
: 自修时写的题目 可是他只有答案我真的不知道我错在哪ˊˋ
: Two events are complementary when
: A. the sum of their probabilities equal one.
: B. the joint probability of the two events is one.
: C. they are both independent and mutually exclusive.
: D. None of the above
: 请教各位板大
: 为什答案不是A
: 而是D啊?
B,B'为互补 <==> (1) P(B联集B')=1 collectively exhausive
(2) P(B交集B')=0 mutually exclusive
A只满足条件(1)
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※ 编辑: protwister 来自: 218.173.2.140 (12/05 09:30)