NPI Rule of Thumbs

This will be a short one as these items would be best placed in a musings column. In fact, I think a couple of them have been in the past. The problem is that I find these interesting and I keep misplacing them so I’m giving them their own article so I can find it easier in the future.

What I have for you today are some NPI Rule of Thumbs with some bonus content at the end. These came from the Latvians and from Ned and are based solely on the 2024 season so expect them to change as we accumulate more data.

Thumb #1 – A team that is around 5 NPI better than their opponent will win the match 88.5% of the time.

Thumb # 2 – A team that is around 2.5 NPI better than their opponent will win the match 75% of the time.

Thumb #3 – Teams that finished the regular season at 60 NPI or higher only lost to teams 55 or lower 10 times during the 2024 season. That was 2% of all matches played under this condition.

Thumb #4 – The lowest Opponent NPI to receive an at-large bid was 0.539.

Thumb #5 – After 6 weeks, if your team is not a QWB team (55.5+ NPI) then they will not receive an at-large bid.

Thumb #6 – After 8 weeks, if your team is not at 57 NPI or higher then they will not receive an at-large bid.

Thumb #7 – After 8 weeks, 85% of the Top 40 teams stayed in the Top 40 at the end of the year.

It will be interesting to see how many of these stay or will be altered slightly after the 2025 season.

The fourth thumb is already dubious to me as Whitworth could have lost their conference tournament final and still received an at-large bid with an Opponent NPI of 0.504.

A couple of more thumb observations:

• The beginning part of the schedule is so important as this is the non-conference portion where you basically create the bulk of your NPI resume. Very few teams play enough quality programs on the back half of their schedule to really cause their NPI to move very much.

• It really looks like the 5 NPI margin is where teams separate themselves from each other.

Bonus Content!

I went back and looked at the largest upset of the 2024 season and it was Marymount (50.022) over Christopher Newport (62.584) in early November. Chris Newport were responsible for 4 of the largest upsets in a bad way in 2024 (Marymount, Heidelberg and UC Santa Cruz twice). (Those NPI numbers included the NCAA Tournament results.)

In that match with Marymount, CNU lost in 5-sets (25-23, 12-25, 19-25, 30-28, 15-9). They had 79 Points to 51 from Marymount. Marymount hit 0.029 for the match. Crazy.