为什么是左偏

问题如下：

An analyst is concerned with the symmetry and peakedness of a distribution of returns over a period of time for a company she is examining. She does some calculations and finds that the median return is 4.2%, the mean return is 3.7%, and the mode return is 4.8%. She also finds that the measure of kurtosis is 2. Based on this information, the correct characterization of the distribution of returns over time is:

选项：

Skewness Kurtosis

A.

Positive Leptokurtic

B.

Positive Platykurtic

C.

Negative Platykurtic

D.

Negative Leptokurtic

解释：