来自孙予明的问题
E(S^2)=D(X)求解概率论求推导E(S^2)=D(X)求解概率论求推导
E(S^2)=D(X)求解概率论求推导
E(S^2)=D(X)求解概率论求推导
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2020-05-20 16:34
E(S^2)=D(X)求解概率论求推导E(S^2)=D(X)求解概率论求推导
E(S^2)=D(X)求解概率论求推导
E(S^2)=D(X)求解概率论求推导
设总体为X,抽取n个i.i.d.的样本X1,X2,...,Xn,其样本均值为Y=(X1+X2+...+Xn)/n其样本方差为S=((Y-X1)^2+(Y-X2)^2+...+(Y-Xn)^2)/(n-1)为了记号方便,我们只看S的分子部分,设为A则EA=E(n*Y^2-2*Y...