[機統] 請問一題統計

看板Math作者 (丁丁是念來過倒)時間9年前 (2015/06/03 22:24), 編輯推噓0(003)
留言3則, 2人參與, 最新討論串3/3 (看更多)
A lumber company has claimed that the standard deviation for the lengths of their 6 foot boards is 0.5 inches or less. To test their claim, a random sample of 17 six- foot boards is selected; and it is determined that the standard deviation of the sample is 0.4. Do the results of the sample support the company's claim? Use α = 0.1. Answer: Since X^2 = 25 > 23.54, reject Ho p-value is between .05and0.10 請問 為什麼X^2是25阿 我怎麼算都是10.24 可是好多地方的解答都是25 感謝 -- ※ 發信站: 批踢踢實業坊(ptt.cc), 來自: 36.224.140.121 ※ 文章網址: https://www.ptt.cc/bbs/Math/M.1433341466.A.47B.html

06/03 23:34, , 1F
解答明顯錯了。觀測值都已符合H0了,怎可能拒絕之?
06/03 23:34, 1F

06/03 23:36, , 2F
25 是 0.5^2 * 16 / (0.4^2),解答誤值數字了。
06/03 23:36, 2F

06/03 23:38, , 3F
感恩!
06/03 23:38, 3F
文章代碼(AID): #1LRmuQHx (Math)
文章代碼(AID): #1LRmuQHx (Math)