,n) ,则-|||-由切比雪夫不等式,有 (|dfrac (1)(n)sum _(i=1)^n({X)_(i)}^2-(mu )_(2)|geqslant c)leqslant () .-|||-(A) dfrac ({mu )_(4)-({mu )_(2)}^2}(n{varepsilon )^2} (B) dfrac ({mu )_(4)-({mu )_(2)}^2}(sqrt {n{s)^2}} (C) dfrac ({mu )_(2)-({mu )_(1)}^2}(n{varepsilon )^2} (D) dfrac ({mu )_(2)-(mu )_(1)}(sqrt {n{sigma )^2}}

,n) ,则-|||-由切比雪夫不等式,有 (|dfrac (1)(n)sum _(i=1)^n({X)_(i)}^2-(mu )_(2)|geqslant s

(B) dfrac (1)(n+1)sum _(i=1)^n(({X)_(i)-overline (X))}^2 .-|||-(C) dfrac (1)(n)s

dfrac (1)(n-1)sum _(i=1)^n(({X)_(i)-overline (X))}^2 .-|||-n-|||-C. sqrt (dfrac

,(X)_(n+1))(ngt 1) 取自总体 sim N(mu ,(sigma )^2) , overline (X)=dfrac (1)(n)sum _(i

12.设总体 sim N(mu ,(sigma )^2), μ,σ^2均未知,则 dfrac (1)(n)sum _(i=1)^n(({X)_(i)-overl

,(X)_(n+1))(ngt 1) 取自总体 sim N(mu ,(sigma )^2) . overline (X)=dfrac (1)(n)sum _(i

设随机变量 X sim N(mu, sigma^2)，利用切比雪夫不等式估计 P|X-mu|A. $\leq \frac{1}{9}$;B. $\geq \fr

设总体 X sim N(mu, sigma^2), mu, sigma^2 均未知，则 (1)/(n) sum_(i=1)^n (X_i - overline(

({S)_(n)}^2=dfrac (1)(n-1)sum _(i=1)^n((x)_(i)--|||-(x))^2 是样本方差,试求满足 (dfrac ({{

(B) (hat {sigma )}^2=dfrac (1)(n)sum _(i=1)^n(({X)_(i)-overline (X))}^2.-|||-(C