NO.PZ2021091302000038
问题如下：
Homoskedasticity is best described as the situation in which the variance of the residuals of a regression is:
选项：
A.zero B.normally distributed C.constant across observations解释：
C is correct. Homoskedasticity is the situation in which the variance of the residuals is constant across the observations.
A为啥不对呢 残差的方差就是一个常数而不是0？我记得残差的均值还是方差是0啊
