题目
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 4.8%, and the modal return is 3.7%. She also finds that the measure of excess kurtosis is 2. Based on this information, the correct characterization of the distribution of returns over time is:
选项
A.Skewness Kurtosis\nPositiveLeptokurtic
B.Positive Platykurtic
C.Negative Platykurtic
D.Negative Leptokurtic
答案
A
解析
The fact that mean>median>mode is consistent with a distribution that is positively skewed. For all normal distributions, kurtosis = 3. Excess kurtosis = kurtosis - 3, which is 0 for a normal distribution. In this case, excess kurtosis = 2, which means kurtosis = 5. This means that the distribution being examined is more peaked than the normal distribution and is said to be leptokurtic.均值>中位数>众数与正偏分布相一致。 对于所有正态分布，峰度=3。过量峰度=峰度-3，对于正态分布为0。 在这种情况下，过量峰度= 2，这意味着峰度=5。这意味着所检查的分布比正常分布峰度更高，因此被认为是尖峰的。