A.等于0
B.等于总平方和
C.完全由观测的随机误差引起
D.完全由各因子水平的差异引起
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A.必然事件
B.不可能事件
C.小概率事件
D.大概率事件
A.原假设为真的条件下检验统计量的概率分布
B.备择假设为真的条件下检验统计量的概率分布
C.观测变量的总体概率分布
D.观测变量的样本分布
A.α
B.β
C.1－α
D.1－β
A.θ^的数值接近于总体参数θ
B.θ^的期望等于总体参数θ
C.θ^的方差接近于总体参数θ
D.θ^的方差接近于总体方差σ2
A.近似等于θ的量
B.随机变量
C.数学期望等于θ的统计量
D.方差固定的统计量
A.正态分布
B.x2分布
C.t分布
D.均匀分布
A.一致性
B.无偏性
C.有效性
D.充分性
A.变量x的标准差
B.变量y的标准差
C.变量x和y两个标准差的乘积
D.变量x和y的协方差
A.平均差大于标准差
B.平均差小于标准差
C.平均差等于标准差
D.二者关系不定
A.左偏分布
B.右偏分布
C.对称分布
D.均匀分布
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