Tiers

While a team’s strength of schedule can give you an idea about how they stack up to competition, how do you know if a team has quality wins or losses?

Tiers can help answer this question.

KenPom defines 2 tiers:

  1. Tier A: a game against a top-50 opponent adjusted for location of the game
  2. Tier B: a game against a top-100 opponent adjusted for location of the game

Why make adjustments for location?

Home court advantage exists in college basketball. KenPom gives a flat 3.75 points for the home team.

The 3.75 points was included in KenPom’s announcement of using AdjEM for ratings prior to the 2016-17 season. It’s explained at the end of this blog post.

For example, in the 2018-2019 season, Virginia would be expected to defeat the average Division-I team by about 34 points on a neutral court.

If Virginia is playing host to the average Division-I team, its AdjEM jumps to about +37. This means at home, Virginia would be expected to defeat the average Division-I team by about 37 points.

This is why adjusting for location is important.

KenPom details this more in this article and shares this example:

Beating the 90th-ranked team on the road is about as difficult as beating the 50th-best team on a neutral floor, which is roughly as difficult as beating the 20th-best team on one’s home floor.

KenPom does hint towards sharing site-specific home-court advantage values in the future too.

Goodbye RPI, Hello NET

Since 1981, the RPI (Rating Percentage Index) was used by the NCAA Selection Committee as one of the main factors in determining at-large selections for the NCAA Tournament.

The NCAA replaced the RPI with the NET (NCAA Evaluation Tool) entering the 2018-19 season. Jordan Sperber does a great job breaking down improvements in this video.