Pairwise Rankings (PWR) and the NCAA hockey tournament outlook

With eight weeks left in the regular season, some teams’ NCAA tournament chances are starting to firm up while others still have the opportunity to climb into or fall out of contention for an at-large bid.

To help get a picture of those possibilities, I ran simulations of the rest of the regular season and calculated each team’s potential Pairwise Rankings (PWR) (which mimic the NCAA’s tournament selection process).

A note on the 2014 PWR

The PWR was changed this year in a few significant ways:

  • RPI now includes a quality win bonus for beating top teams
  • RPI now weights home losses/road wins higher than home wins/road losses for the win percentage criterion
  • PWR no longer includes the Teams Under Consideration criterion

By shifting the credit for strong wins from a PWR criterion (TUC) to the RPI (QWB), the other PWR criteria are deemphasized. With only three criteria in PWR and RPI as the tie-breaker, PWR will only deviate from RPI when head-to-head results come into play.

Teams that are almost a lock

A few teams’ performances have already earned them strong enough RPIs that they’re almost locks for at-large bids to the NCAA tournament. That level seems to be above about a 57 RPI index.

minnesotaendofseason

#1 Minnesota (61.2 RPI) currently wins all of its PWR comparisons.  Even if the Gophers were to win only 4 of their remaining games, they would still end the regular season in the top 10.

bcendofseason

#2 Boston College (59.97 RPI) currently wins 57 of 58 PWR comparisons. Winning 4 of its remaining games would result in a top 10 regular season finish, while winning only 2 would still leave the Eagles in a likely position for an at-large bid.

quinnipiacendofseason

#3 Quinnipiac (57.63 RPI) currently wins 56 of 58 PWR comparisons. The Bobcats need to win 4 of their remaining 8 games to be certain to be in position for an at-large bid at the end of the regular season, though could still be in contention with just 2 wins.

Teams that are almost out of contention

On the other end of the RPI rankings, some teams have performed poorly enough to date that they have very little chance of making the tournament at-large. That line seems to be below about a 49 RPI index.

alaskaendofseason

#36 Alaska (49.39 RPI) currently wins 24 of 58 PWR comparisons. Even if Alaska won out, they would likely be just on the outside of an at-large bid at the end of the regular season.

bentleyendofseason

#39 Bentley (49.1 RPI) currently wins 19 of 58 PWR comparisons. Winning out would not provide Bentley enough of a boost to make the tournament at-large by the end of the regular season.

The outlook is similarly grim for the 21 teams below Bentley in RPI:

Bemidji State
Michigan State
Michigan Tech
Massachusetts
Merrimack
Harvard
Connecticut
Boston University
Canisius
Dartmouth
RIT
Princeton
Colorado College
Penn State
Holy Cross
Robert Morris
American Int’l
Niagara
Sacred Heart
Alabama-Huntsville
Army

Methodology

Each forecast is based on at least one million monte carlo simulations of the games in the described period. For each simulation, the PairWise Ranking (PWR) is calculated and the results tallied. The probabilities presented in the forecasts are the share of simulations in which a particular outcome occurred.

The outcome of each game in each simulation is determined by random draw, with the probability of victory for each team set by their relative KRACH ratings. So, if the simulation set included a contest between team A with KRACH 300 and team B with KRACH 100, team A will win the game in very close to 75% of the simulations. I don’t simulate ties or home ice advantage.

Resources