With the unveiling of the 2006-07 USCHO.com Division I Women’s Pairwise Rankings (PWR), it’s time to discuss the new twists in the NCAA tournament selection criteria.
So how are the eight teams selected for NCAAs?
Automatic bids go to the conference tournament champions of the ECACHL, WCHA, and Hockey East. There are five at-large selections determined by an objective NCAA criteria, which is mimicked by the PWR. The top four teams will earn home ice for NCAA quaterfinal games.
The autobid winners will not be known until March, so any current bracket projections (to be posted on the D-I Women’s Blog with comments) will take the top eight teams, with the understanding that the teams ranked 6th through 8th could be bumped out by autobid winners.
What are the NCAA selection criteria this season?
• Rating Percentage Index (RPI) [won-lost record (30 percent), opponents’ winning percentage (24 percent) and opponents’ opponents’ winning percentage (46 percent)];
• Head-to-head competition;
• Results versus common opponents;
• Results during the last 16 games; and
• Results against teams at .500 or above in the RPI.
See the PWR Individual Comparisons Table to see examples of how teams are compared and ranked using the NCAA selection criteria.
There are two criteria changes from last season, both of which are technical details in the calculation of the RPI. First, the weights in the RPI are now 30-24-46 for the three components instead of 35-50-15. The second change is that all games which lower a team’s RPI are omitted from the RPI calculation. In the past two seasons, up to four games and all postseason games were omitted.
So what are these differences between the current PWR and the NCAA criteria?
A few caveats you need to keep in mind when perusing the PWR, which attempt to model the NCAA’s criteria.
•Last 16 Games
Unlike men’s hockey, women’s hockey still uses record in the last 16 games as an NCAA selection criterion. The current PWR are always calculated using the last 16 games available, rather than what will likely be the last 16 games at the end of the season. Many teams have only just begun to play those last 16 games.
When I make bracket projections, I will try to anticipate the last 16 games at the end of the season.
•Record vs. Teams with RPI > .500
In any volatile season, the subset of teams with RPI above .500 changes every week. This matters a lot for the PWR, especially for teams in conferences that play opponents four times.
USCHO’s RPI calculations do not yet drop all games that lower RPI, as the NCAA does. When this discrepancy has an impact on the RPI for the top teams, I will make note of it in the bracket projections.
What are the caveats for how the NCAA pairs teams?
In the brief history of the eight-time NCAA women’s hockey tournament, the committee has maintained perfect bracket integrity — that is ranking the eight qualifying teams and pairing them 1v8, 2v7, 3v6, 4v5.
The one area where the committee’s subjectivity may come into play is in deciding whether to sacrifice bracket integrity to avoid intraconference matchups. In the past two seasons, seedings have worked out nicely so that the committee did not have to decide between the two. That good luck is not going to last forever. I will provide further discussion on the advantages and disadvantages of various pairings as the season progresses.