问题如下：
When dealing with two random variables, how is coskewness interpreted?
选项：
解释：
Coskewness measures the likelihood of one variable taking a large directional value whenever the other variable is large in magnitude. When there is no sensitivity to the direction of one variable to the magnitude of the other, the coskewness measures are 0.
老师，这道题的答案看的不是很明白，什么又叫做directional value呢，麻烦老师用中文在讲解一下这道题，谢谢
