NO.PZ2019040801000011
问题如下：
A distribution that has a smaller percentage of small deviations from the mean and a smaller percentage of extremely large deviations from the mean:
选项：
A.
is positively skewed.
B.
is a symmetric distribution.
C.
has negative excess kurtosis.
D.
has positive excess kurtosis.
解释：
C is correct
考点：Skewness and Kurtosis
解析：当一个分布的mean附近位置的比例比较高，离mean很多标准差的位置分布比例也比较高，也就是尖峰肥尾的时候，峰度会比较高；反之（本题的情况）峰度会比较低。
老师好，1、smaller percentage of small deviations from the mean 不是说距离均值较小离散的比例较小，应该是不集中在均值呀？理解不出是尖峰的意思啊？
2、a smaller percentage of extremely large deviations from the mean 不是说距离均值较大离散程度的比例较小，这个是集中在均值，也不是说肥尾啊？
