It is considered difficult to analytically prove whether sample probability weighted moments with discrete series are unbiasedestimators.
人们普遍认为要从理论上通过数学分析的方法来论证不连序系列样本概率权重矩的偏倚性是很困难的。
2
While not all useful estimators are unbiased, virtually all economists agree that consistency is a minimal requirement for an estimator.
虽然并不是所有的有用的估计量是无偏的，但是，一致性则是经济学家对估计量的最低要求。
3
The regression equation for incomplete data is established, and the best unbiased integral estimators of the regression parameters and their covariance matrix are also given.