设是取自总体X的一个简单样本，则的矩估计是 - 查题网

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成人高等教育 / 概率统计

设 ${ X }_{ 1 }{ ,X }_{ 2 }{ ,\cdots ,X }_{ n }$ 是取自总体X的一个简单样本，则 $E({ X }^{ 2 })$ 的矩估计是

A、
${ S }_{ 1 }^{ 2 }=\frac { 1 }{ n-1 } \sum _{ i=1 }^{ n }{ { ({ X }_{ i }-\overline { X } ) }^{ 2 } }$
B、
${ S }_{ 2 }^{ 2 }=\frac { 1 }{ n } \sum _{ i=1 }^{ n }{ { ({ X }_{ i }-\overline { X } ) }^{ 2 } }$
C、
${ S }_{ 1 }^{ 2 }+{ \overline { X } }^{ 2 }$
D、
${ S }_{ 2 }^{ 2 }+{ \overline { X } }^{ 2 }$

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概率统计

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