Re: [問題] 97中央企研統計

看板Grad-ProbAsk作者 (jass)時間17年前 (2009/03/19 15:49), 編輯推噓2(202)
留言4則, 3人參與, 最新討論串2/2 (看更多)
※ 引述《xiang1989215 (let it be)》之銘言: : Suppose the relationship between applied stress x and time-to-failure Y is : described by the simple linear regression model with true regression line : E(y)=100-3.92x and σ2 =2. Let Y1 denotes an observation on time-to-failure : made with x=15 and Y2 denotes an independent observation made with x=14, find : the probability that Y1 exceed Y2, i.e.,P(Y1>Y2)=? : 請問上述問題該如何解? Y1 ~ N(100-3.92*15 = 41.2 , 2) Y2 ~ N(100-3.92*14 = 45.12, 2) Y1-Y2 ~N(41.2-45.12 = -3.92 , 2+2 = 4 ) P(Y1>Y2) = P(Y1-Y2>0) = P(Z> 3.92/2 =1.96 ) = 0.025 -- ※ 發信站: 批踢踢實業坊(ptt.cc) ◆ From: 61.58.85.190

03/19 15:59, , 1F
P(Z>1.96)=0.025?
03/19 15:59, 1F

03/19 16:06, , 2F
謝謝^^"
03/19 16:06, 2F

03/19 16:24, , 3F
Y1-Y2 = 3.92 :P
03/19 16:24, 3F
※ 編輯: hahakelly 來自: 61.58.85.190 (03/19 16:35)

03/19 16:35, , 4F
一直打錯T^T 謝謝樓上兩位
03/19 16:35, 4F
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