Xin (a,b) =phi (dfrac (b-mu )(sigma ))-Phi (dfrac (a-mu )(sigma ))-|||-C) (x)=Phi (dfrac (x-mu )(sigma )) .-|||-) |x-mu |leqslant k0 =2Phi (k)-1(kgt 0)

(overline (X))=dfrac ({sigma )^2}(n)-|||-C. (overline (X)-mu )=dfrac ({sigma )^2

已知总体X服从[ mu ,(sigma )^2] ( [ mu ,(sigma )^2] 已知,[ mu ,(sigma )^2] 未知) ,[ mu ,(si

设随机变量X的分布函数为(X)=dfrac (1)(2)Phi (x)+dfrac (1)(2)Phi (dfrac (x-4)(2))(X)=dfrac (1

... +({X)_(n)}^2)-|||-;(5) (mu )^2+dfrac (1)(3)((X)_(1)+(X)_(2)+(X)_(3))-|||-;(6

4.设总体 sim N(mu ,(sigma )^2), x1,x2,x3为来自X的样本 hat (mu )=dfrac (1)(4)(x)_(1)+b(x)_

(B) dfrac (sqrt {n)(overline (X)-mu )}(S)sim t(n-1).-|||-(C) dfrac (sqrt {n)(ove

(B) .dfrac ({mu )_(0)I}(2pi R)+dfrac (3{mu )_(0)I}(8R)-|||-(c) dfrac ({mu )_(0)I

设随机变量 X sim N(mu, sigma^2), 则随着 sigma 的增大, 概率 P(|X-mu|A. 单调增加B. 单调减少C. 保持不变D. 增减

5.设 ,b,c,mu gt 0 ,曲面 =mu 与曲面 dfrac ({x)^2}({a)^2}+dfrac ({y)^2}({b)^2}+dfrac ({

(B) (mu ,dfrac (1)(sqrt {2pi )})-|||-(C) (mu ,dfrac (1)(2)), (D)(0,σ).