作者Vanisha (no)
看板Statistics
標題[問題] 變異數問題
時間Fri Aug 12 20:16:29 2011
The random variable X is defined by taking the square of the score obtained
by rolling an unbiased dice once.
計算出
x= 1 4 9 16 25 36
p(X=x) 1/6 1/6 1/6 1/6 1/6 1/6
F(x) 1/6 2/6 3/6 4/6 5/6 6/6
E(X)= 15.17
Var(X)用 1x(1-15.17)^2 +.....+ 1x(36-15.17)^2 /6
去算的答案跟解答379.14不符合
請問是哪邊出錯了呢? 謝謝~
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