作者sparrow620 (可遇不可求′-`y-～)
看板Grad-ProbAsk
标题[商管] 有一题统计想请教
时间Fri Nov 26 19:49:23 2010
假设有一销售员的monthly salary 服从uniform分配
so let r.v X~U(50000,70000)
a.What are the expected value and standard deviation of his monthly salary?
b.If he has to pay alimony to his ex-wife and he has the following two plans
to choose from：(1) 20% of his monthly salary (2) 40% of what is left for
him after substracting $30000 from the realized monthly salary. Which plan
should he choose?
a小题按uniform distribution的特性可以得知
μ=(50000+70000)/2=60000
σ={(70000-50000)/12}^1/2
问题是b小题 那个(2) 不懂题意
是由他真实的薪水扣除30000後，他所剩的薪水的40% ???
很久没碰统计了一时脑袋卡住...
有人可以解答吗？ 谢谢
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隔年在２４岁发明了积分学。
但是他害很多人在１９岁时微积分被当，到了高等微积分再次被当...Orz
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1F：推 serflygod:推你的签名档 11/26 20:10
2F：→ sparrow620:已解决 b小题EX值一样 再算var应该就可以选择了 11/26 23:27