设X1,X2.Xn来自总体为N(0,σ^2)分布的样本则且随机变量Y=C(∑xi)^2~x^2(1)则常数C是
问题描述:
设X1,X2.Xn来自总体为N(0,σ^2)分布的样本则且随机变量Y=C(∑xi)^2~x^2(1)则常数C是
答
X1,X2.Xn来自总体为N(0,σ^2)=>∑xi~N(0,nσ^2)=>∑xi/√(nσ^2)~N(0,1)=>[∑xi/√(nσ^2)]^2~x^2(1)=>
C=nσ^2