作者vfive (哈哈)
看板TransPSY
标题[统计] 嘉大行销所考古题
时间Mon Mar 1 23:30:13 2010
In a lottery game, a player selects 6 inteners out of the first 49 positive
integers. The sposor then ramdomly selects 6 out of the first 49 positive
integers. Cash prizes are given to a player who match4, 5 or 6 inteners.
Lex X equal the number of inteners selected by a player that match inteners
selectd by the sponder.
(1) State the p.d.f X
(2) Calculate the mean,variance and standard deviation X.
(3) What value of X is mostly likely to occur?
(4) On March,2005, the jackpot was worth $450,000,000. When the prize is large,
a lot of bets are placed. Out of 25,000,000 bets that were placed,3 people
matched 6 numbers and matched 5 numbers,22187 matched 4 numbers.
Are these numbers of winners consistent with the probability model?
请问这题是二项分配吗?
f(x)=(6Cx)P^XQ^(n-x)吗 p=6/49 x=0.1.2.3.4.5.6
第四小题则无头绪
谢谢~~~~
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1F：→ a761223:不好意思，刚刚有贴一篇写错了，还正在想。 03/02 20:21
2F：→ a761223:我在想，如果是不放回的话，那好像不是二项分配耶... 03/02 20:46
3F：→ a761223:好像是超几何分配的样子。 03/02 20:52
4F：→ a761223:超几何分配的话，有其固定的函数形式跟计算平均数、变异数 03/02 23:58
5F：→ a761223:的公式，你可以参考自己的统计用书或查资料。 03/02 23:58
6F：→ a761223:结果有帮到你的忙吗？ XD 不好意思我懒得去查超几何的公式 03/06 23:07
7F：→ a761223:第四小题是不是要代进去算看看有没有符合次数分配？ 03/06 23:08