Skewness

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.
Video description

This video introduces the concept of skewness of a random variable, providing some intuition behind the mathematical construct of this concept. Check out https://ben-lambert.com/econometrics-course-problem-sets-and-data/ for course materials, and information regarding updates on each of the courses. Quite excitingly (for me at least), I am about to publish a whole series of new videos on Bayesian statistics on youtube. See here for information: https://ben-lambert.com/bayesian/ Accompanying this series, there will be a book: https://www.amazon.co.uk/gp/product/1473916364/ref=pe_3140701_247401851_em_1p_0_ti