NCAA NET Rankings Explained and How to Use Them When Betting College Basketball
By Peter Dewey
The 2021-22 season is the fourth season of the NCAA Evaluation Tool (NET) rankings being used as the primary sorting tool for evaluating teams; replacing RPI as the primary option. It uses just two components: Team Value Index and an adjusted net efficiency rating.
For bettors, NET rankings can be a useful tool to use when comparing two similar teams to help decide who has the edge in the NCAA Tournament.
NCAA Division I men’s and women’s basketball use selection committees when deciding the field for the NCAA Tournament championship, and NET rankings help simplify some of the debate that can put teams in the field, and where they deserve to be seeded each year.
Here is our complete guide of the NCAA Evaluation Tool and how you can use it to help you bet on college basketball.
What are NCAA NET rankings?
The NCAA Evaluation Tool is composed of two parts, Team Value Index and an adjusted net efficiency rating.
Unlike RPI, which did not give the full scope of a team’s success, NET Rankings takes into account several factors that determine where a team should be placed among the field that season. Those factors include game results, game location and opponent, net offensive and defensive efficiency, and the quality of wins and losses.
NET Rankings are an evaluation tool that works for all of the teams across different conferences in the NCAA. With mid-major and high-major schools facing different levels of competition in different environments, NET rankings are used to hold all teams to the same evaluation when looking for seeding in the NCAA Tournament.
While NET rankings are important, it is still just one of the tools used by the selection committees to determine which teams receive at-large bids for March Madness and how each team is seeded in their respective regions.
Since teams that win their conference title are given automatic bids to the NCAA Tournament, the NCAA Evaluation Tool helps the committee decide which at-large teams deserve to be included in the field of 68.
What’s the difference between NET rankings and RPI?
The NCAA had used RPI as the primary evaluation tool since the 1981 season before changing to NET rankings four seasons ago. There were certain flaws with the RPI method, such as not accounting for margin of victory, that led to criticism of it being the primary tool to decide a team’s fate in March.
The Ratings Power Index (RPI) used three components:
- A team's winning percentage
- Average opponent's winning percentage
- Average opponent's opponents' winning percentage
The difference between NET rankings and RPI is that NET rankings take into account much more through the Team Value Index and an adjusted net efficiency rating. These factors include game results, game location and opponent, net offensive and defensive efficiency and the quality of wins and losses.
What’s the difference between NET rankings and KenPom?
KenPom, which is a separate ranking developed by Ken Pomeroy, looks at several statistical formulas that come together to form the Adjusted Efficiency Margin for every team. The better Adjusted Efficiency Margin, the higher the team is ranked.
Essentially, the goal of Adjusted Efficiency Margin is to show how much each team would outscore an average college basketball team per 100 possessions. Pomeroy’s ranking system incorporates statistics including shooting percentage, margin of victory and strength of schedule, to calculate each team’s efficiency independent of injuries or emotional factors in the game.
While NET uses offensive and defensive efficiency as part of its formula, there are still several other factors (game locations for example) that differ from KenPom. Both rankings can be beneficial for bettors as they can find out if both metrics value teams in a similar fashion before placing a wager on them.
NET Rankings vs. AP Top 25
While the NCAA Evaluation Tool is composed of several different factors, it does not have an official ranking released weekly like the AP Top 25.
The AP Poll comes by polling 62 sportswriters and broadcasters from across the nation on the country’s top teams. While the AP Poll can give fans a glimpse into who the top teams are, it does not have the statistical formula that NET rankings possess.
How are NET rankings calculated?
NET rankings are calculated by looking at each team’s Team Value Index and an adjusted net efficiency rating.
Team Value Index is based on game results, taking into account the game’s location, the team’s opponent and who ended up coming away with the victory.
Adjusted net efficiency rating takes into account more factors, looking at a team’s offense and defense:
Calculating Offensive Efficiency:
- FGA - offensive rebounds + turnovers + .475 (FTA) = Total Possessions
- Total Points/Total Possessions = Offensive Efficiency
Calculating Defensive Efficiency:
- Opponent FGA - opponent offensive rebounds + opponent turnovers + .475 (opponent FTA) = Total Opponent Possessions
- Opponent Total Points/Opponent Total Possessions = Defensive Efficiency
In May of 2020, it was announced that the NET will no longer use winning percentage, adjusted winning percentage and scoring margin.
What college basketball rankings matter most?
While the NET rankings is arguably the most important because it is what the committee uses it to determine the field for the NCAA Tournament, there are other rankings that are considered as well.
For bettors, finding teams that rank high in several different rankings can be a sign of a truly good team. If a team ranks high in one metric and poorly in others, there can be a cause for concern on the team’s true value. In order to succeed in betting on college basketball games, it is important to factor in several rankings to evaluate each team.
What do NET rankings mean when betting?
As mentioned above, NET rankings are a large piece of the puzzle, but not the only one, when it comes to betting on college basketball.
While the NET is an important and complex analytical model, it isn’t the end all be all when it comes to betting on games. Certain teams match up better with others based on their play