题目
Which of the following statements related to the F-distribution and chi-squared distribution is wrong? Both distributions:
选项
A.Are asymmetrical.
B.Are bound by zero on the left.
C.Are defined by degrees of freedom.
D.Have means which are less than their standard deviations.
答案
D
解析
There is no consistent relationship between the mean and standard deviation of the chi-squared distribution or F-distribution.卡方分布或F分布的平均值和标准偏差之间没有一致的关系。