[理工] [統計] 成大

看板Grad-ProbAsk作者 (J大)時間13年前 (2011/01/26 23:05), 編輯推噓1(101)
留言2則, 1人參與, 最新討論串1/1
這成大的考古題沒有答案... 想上來與版上的大大一起討論討論 是99製造的!! http://ppt.cc/;0np 裡面的第1、2、4我都有點不太確定.. 2. A fault-tolerant system that processes transactions for a financial service use three separate computers. If the operating computer fails , one of the two spares can be immediately switched online. After the second computer fails , the last computer can be immediately switched online. Assume the probability of failure during any transaction is 1O^-8 (Q) State the proper probability model for the number of transactions X before all three computers have failed. Write out the probability function and cumulative distribution function of X. 4. A manufacturer of automobile batteries claims that the distribution of the life of its battery has a mean of 54 months and a standard deviation of 6 monWhat is the probability the consumer group's sample has a mean life of a mean life of 52 or fewer months? ths. But the population mean is 50 months and population standard deviation is7 months. Suppose a consumer group decides to check the claim by purchasing a sample of 50 of these batteries. No knowledge of the shape of the distribution of the life. (Q). Try to describe the sampling distribution of the mean life of a sample of 50 batteries 不知道是不是我英文太差= = 第二題是不大確定該用什麼分配 第四題該用54還是52去估呢?? 感謝大家... -- ※ 發信站: 批踢踢實業坊(ptt.cc) ◆ From: 124.12.57.122

01/27 18:53, , 1F
第一題a.二項 b.poission 第二題我覺得是2項
01/27 18:53, 1F

01/27 18:55, , 2F
第四題 中央極限定理 Xbar
01/27 18:55, 2F
文章代碼(AID): #1DG3WSBA (Grad-ProbAsk)