College hockey’s venerable Pairwise system will soon be replaced with something called the NCAA Percentage Index, or NPI.
That transition has been in the works over the couple of years, and it looks like the NCAA Men’s Ice Hockey Committee is ready to officially make the change.
The final makeup of the formula is still being worked out, but expect the new system to be in place by the coming season.
The Pairwise has seen many changes to its makeup over the last 30-plus years it’s been used, but at heart, it’s a hands-off, deterministic method of selecting the field for the NCAA Tournament. Put the parameters into the computer, and it spits out a ranking. Though the criteria that go into the Pairwise have been tweaked over the years, at the end of the day, the criteria is set in stone before the season starts, and no subjective opinions are used in selecting the field.
In that regard, nothing changes. Instead, the NPI essentially replaces the RPI, and will be used exclusively without any other criteria. RPI is just one component of the Pairwise, but over the years, its importance has grown with the elimination of other criteria. And any philosophical choices — such as weighting road wins more than home wins, overtime weights, factoring “quality wins,” and so on — were just rolled into the RPI.
The same will hold true of the NPI, which will also consider all of those factors. Gone will be the final holdover criteria from the Pairwise — namely Record vs. Common Opponents, and Head-to-Head record. Those criteria had minimal importance in recent years, and rarely played a factor.
As for the bottom line, don’t expect much to change. The difference between NPI and RPI is enough to move the needle one place or two for some teams, which could obviously have some impact on which team makes the NCAA Tournament, but there won’t be a drastic difference.
The Committee is still currently working through how to weigh the various factors that will go into the NPI calculation, though again, those were already considerations in calculating the RPI as well. It’s possible the home-road weighting will be changed from the current 80/120, and OT weightings changed from the current 67/33. Those things are still to be determined.
There has also been a proposal to eliminate the home/road weightings when it comes to conference tournament playoff games. That will be discussed, but it’s uncertain how much backing it has.
At its root, NPI is made up of 25 percent your own record, while the other 75 percent is “strength of schedule.” The SOS is determined from an iterative algorithm, similar to what the College Hockey News Power Ratings (KRACH) uses.
NPI is used in women’s hockey as a replacement for RPI, but women’s hockey still uses a Pairwise with other components.
Other sports have also transitioned away from RPI to NPI in recent years, with each sport making its own tweaks. RPI was first created by the NCAA in the early 1970s.
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