Skewness
Skewness of a Distribution
In this section, the concept of skewness in a distribution is discussed, highlighting how skewness can be represented by the third central moment of a distribution.
Understanding Skewness
- Skewness refers to the asymmetry in a distribution, with positively skewed distributions having a long positive tail.
- Positively skewed distributions are characterized by an extended positive tail towards the x-direction.
- Skewness can be quantified using the expectation of (x - mean)^3.
- This calculation helps determine whether a variable is positively skewed or symmetric.
- For symmetric distributions, the average value of (x - mean)^3 is zero.
- Symmetric distributions exhibit no skewness as the average value is centered around zero.
Calculating Skewness
- Skewness can be measured by dividing the third central moment by sigma squared and raising it to power three over two.