Now that the NFL regular season is wrapped up, it is time to take a look at how competitively balanced the NFL was last season. In order to do this, I am going to look at the NFL season statistically as a sample and as a population - mainly for comparison purposes. Additionally, I will take a look at the conferences separately in terms of competitive balance. The data comes from profootball-reference.com.
There are a lot of ways to measure competitive balance, and I have chosen to use a simple measure called the Noll-Scully Competitive balance measure. By competitive balance we are looking at how well a league's standings are in relation to a league where wins and losses are determined randomly. Here is a step-by-step guide if you want to calculate this on your own. As a reference, here is the Noll-Scully using a sample or a population for the NFL since 1981.
For the NFL in 2013 the Noll-Scully was 1.527 (population) and 1.551 (sample). If you click on the link in the last sentence above, you will notice that the NFL's competitive balance for this past season is very similar to recent seasons. Additionally notice that the NFL and the NCAA FBS "leagues" measure of competitive balance are also very similar.