Known commonly as NCAA Evaluation Tool, the NCAA NET Rankings came to replace the Rating Percentage Index (RPI) as the most important selection instrument for the NCAA’s March Madness tournament. This tool was first implemented before the 2018–19 season of men’s college basketball.
The former RPI system considered the following data to rank NCAA teams: the winning percentage, the average opponent’s winning percentage and the winning percentage of the opposition’s previous opposition. This has changed since the adoption of this new ranking tool. The NET rankings have two main constituents: Team Value Index and the Team’s NET efficiency.
On one hand, The Team Value Index is a feature based on results that rewards teams for winning over quality opponents, especially away from home. On the other hand, the NET efficiency is an index regulated for the strength of the opponent and location (home/away/neutral), that represents the difference of points scored and allowed per 100 possessions.
NET used to also take into consideration winning percentage, adjusted winning percentage and scoring margin, such as seen in the NCAA’s tweet below. But all of that was changed in the 2020-21 season, after the NCAA Division I men’s basketball committee did some consultation sessions with Google Cloud Professional Services, the only indicators taken into consideration now are the two previously mentioned Indexes.