题目

设总体Xsim N(0,2)，(X_(1),X_(2),... X_(9))为来自总体X的简单随机样本，则k=（）时，(ksum_(i=1)^3X_(i)^2)/(sum_(i=4)^9X_{i)^2}sim F(3,6).A. (sqrt(2))/(2);B. 2;C. sqrt(2);D. (1)/(2).

设总体$X\sim N(0,2)$，$(X_{1},X_{2},\cdots X_{9})$为来自总体X的简单随机样本，则k=（）时，$\frac{k\sum_{i=1}^{3}X_{i}^{2}}{\sum_{i=4}^{9}X_{i}^{2}}\sim F(3,6)$.

A. $\frac{\sqrt{2}}{2}$;

B. 2;

C. $\sqrt{2}$;

D. $\frac{1}{2}$.

题目解答

B. 2;