For those curious how our NBA power rankings work, we combine four different measurements: win-loss ratio, 10 game win-loss ratio, net rating, and the Statsplit Ranking. Each of these utilizes a min-max normalization across each category and composes 25% of the total score. From all of that we get our final power ranking for each team.
So, to show how the ranking works, we'll go over an example. Let's say the Atlanta Hawks have the worst record in the league at 8-32 and they have gone 4-6 in their past ten, with the worst net rating, and the second worst Statsplit rating.
Since they have the worst record in the league they get a score of 0 for the win-loss ratio. This is due to the min-max normalization which bounds the values between 0 and 1. The best team in the category gets a 1, while the worst gets a 0. All teams in between get some value between 0 and 1.
Let's say for the past 10 games, there is a team that is 10-0 and a team that is 0-10. Thus, since the Atlanta Hawks went 4-6, they receive a score of 0.4 for this category.
For net rating which subtracts offense rating from defense rating, we assign the Hawks a 0 because they are once again the worst team in the league.
The Statsplit rating is the scoring system that we use for our college football rankings. It is used to reward teams more for upsets than expected wins and punish teams less when they lose to quality teams. Our Hawks have the second worst rating. Let's say they have a rating of 510. The worst team has a rating of 500. The best team has a rating of 1500. Using our normalization, the Hawks would have a score of 0.01 for this category.
Last to get the final ranking, we add the scores from all four categories and then divide by 4. This weights all categories evenly. The reason these are power rankings is that the last 10 win-loss ratio and the Statsplit rating tend to favor teams that can put together a winning streak and punish teams that go on long losing streaks. By adding everything and taking the average, the Hawks have a final score of .1025.
Hopefully that clarifies the process that I use to compute our power rankings. Check out Statsplit every Friday to see the latest up-to-date power rankings.
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