A. $\Phi(y);$
B. $\Phi(\frac{y-np}{\sqrt{np(1-p)}});$
C. $\Phi(y-np);$
D. $\Phi(\frac{y-np}{np(1-p)})。
设X_(1),X_(2),...,X_(n)相互独立,且都服从标准正态分布N(0,1),则sum_(i=1)^nX_(i)^2simchi^2(n-1).A.
5 判断 设随机变量X_(1),X_(2),...,X_(n),...相互独立,且X_(i)sim U(2,4)(sim i=1,2,...),则lim_(n
设X_(1),X_(2)...,X_(n)是来自总体X的样本,则(1)/(n-1)sum_(i=1)^n(X_(i)-overline(X))^2为().A.
1.设X~N(0,1),X_(1),X_(2),X_(3),X_(4),X_(5)为其样本,求(2X_(5))/(sqrt(sum_(i=1)^4)X_{i^2
设X_(1),X_(2),...,X_(n)是来自总体X的样本,则(1)/(n-1)sum_(i=1)^n(X_(i)-overline(X))^2是()A.
3.设n个随机变量X_(1),X_(2),...,X_(n)独立同分布,D(X_(1))=sigma^2,overline(X)=(1)/(n)sum_(i=1
(1)/(5)sum_(i=1)^n(X_(i)-lambda)^2, minX_{1),X_(2),...,X_(n)}中不是统计量的是____.三、设总体
1.6 总体X-N(mu,sigma^2),x_(1),x_(2),...,x_(n)为其样本,bar(x)=(1)/(n)sum_(i=1)^nx_(i),s
若 Y=X_(1)+X_(2),X_(i) sim N(0,1),i=1,2,则()A. $E(Y)=0$;B. $D(Y)=2$;C. $Y \sim N(0
设X_(1),X_(2),...,X_(n)为总体X的简单样本,则样本均值overline(X)=(1)/(n)sum_(i=1)^nX_(i).A. 对B.