题目
4.（单选题，10.0分）设X_(1)，X_(2)，X_(3)，X_(4)为来自总体X的样本，则下列（）不是总体均值无偏估计量.A. hat(mu)_(1)=0.2X_(1)+0.3X_(2)+0.1X_(3)+0.4X_(4)B. hat(mu)_(2)=X_(1)C. hat(mu)_(3)=0.2X_(1)+0.2X_(2)+0.2X_(3)+0.2X_(4)D. hat(mu)_(4)=2X_(1)+X_(2)-2X_(3)
4.（单选题，10.0分）设$X_{1}$，$X_{2}$，$X_{3}$，$X_{4}$为来自总体X的样本，则下列（）不是总体均值无偏估计量.
A. $\hat{\mu}_{1}=0.2X_{1}+0.3X_{2}+0.1X_{3}+0.4X_{4}$
B. $\hat{\mu}_{2}=X_{1}$
C. $\hat{\mu}_{3}=0.2X_{1}+0.2X_{2}+0.2X_{3}+0.2X_{4}$
D. $\hat{\mu}_{4}=2X_{1}+X_{2}-2X_{3}$
题目解答
答案
C. $\hat{\mu}_{3}=0.2X_{1}+0.2X_{2}+0.2X_{3}+0.2X_{4}$