9.设总体服从正态分布N(μ,1),且μ未知,设-|||-X1,X2,···,Xn为来自该总体的一个样本,记-|||-overline (X)=dfrac (1)(n)sum _(i=1)^n(X)_(i)(S)^2=dfrac (1)(n-1)sum _(i=1)^n(({X)_(i)-overline (X))}^2 则^H的置信水平-|||-为 1-a 的置信区间公式是-|||-A (overline (X)-(z)_(dfrac {alpha )(2)}sqrt (n),X+(z)_(dfrac {alpha )(2)}+dfrac (1)(sqrt {n)})-|||-B (overline (X)-(t)_(dfrac {a)(2)}(n-1)dfrac (1)(sqrt {n)},overline (X)+(t)_(dfrac {a)(2)}(n-1)dfrac (1)(sqrt {n)}-|||-C (overline (X)-(t)_(dfrac {a)(2)}(n-1)dfrac (S)(sqrt {n)},overline (X)+(t)_(dfrac {a)(2)}(n-1)dfrac (S)(sqrt {n)}-|||-D (overline (X)-(z)_(dfrac {alpha )(2)}dfrac (s)(sqrt {n)},overline (X)+(z)_(dfrac {alpha )(2)}dfrac (s)(sqrt {n)})

设总体服从正态分布N(mu,1)，且mu未知，设X_1,X_2,...,X_n为来自该总体的一个样本，记overline(X)=(1)/(n)sum_(i=1)

1.设X1,X2,···,xn来自总体X的样本, (X)=(sigma )^2, overline (X)=dfrac (1)(n)sum _(i=1)^n(X

设X1,X2,···, _(n)(ngeqslant 2) 为来自总体N(μ,1)的简单随机样本,-|||-记 overline (x)=dfrac (1)(n

(16)设X1,X2,···,xn为来自标准正态总体X的简单随机样本,记 overline (X)=dfrac (1)(n)sum _(i=1)^n(X)_(i

5.11 设(X1,X2,···Xn, _(n)+1) 是正态总体N(μ,σ^2)的样本, overline (X)=-|||-dfrac (1)(n)sum

(8)设X1,X2,··· _(n)(ngeqslant 2) 为来自总体N(μ,1)的简单随机样本,记 overline (X)=dfrac (1)(n)su

1.设总体 sim N(M,(sigma )^2) ,μ未知而σ^2已知,X1,X2,···,Xn是X的样本, overline (X)=dfrac (1)(n

4.样本X1,X2,···Xn来自总体 sim N(0,1) , overline (X)=dfrac (1)(n)sum _(i=1)^n(X)_(i) ,

9.设X1,X2,···,Xn,·,xn是来自正态总体N (0,σ^2)的一个样本,且已知随机变量 =-|||-((sum _{i=1)^m(x)_(i))}^

4.设总体 sim N(mu ,(sigma )^2), x1,x2,···,xn为样本,证明 overline (x)=dfrac (1)(n)sum _(i