Month: March 2018

I was curious to see whether the passage of time has changed how the Tournament Committee makes its seeding decisions.  Does an 0.60 RPI have the same meaning in 2018 as it did at the beginning of the 21st century?  Do teams with an 0.60 in 2018 get about the same seeding as they would have received in 2000?

To address this question I simply added a term that measures the number of years since 2000 to my standard model.  The effect is significant and uniform across all three types of conferences.  This chart presents the estimated relationship between RPI and seeding for major conference teams setting the elapsed time variable to its extreme values of one (2001) and 17 (2017).

The difference is substantial.  Since 2000, the Committee has reduced the seedings they grant by about 1.3 ranks.¹ Another way to look at this is to ask how much greater does a team’s RPI need to be in 2017 to get the same seeding it would have gotten in 2001. In 2001, a six seed would have required an RPI of 0.602; in 2017, that floor had been raised to 0.613. In the RPI rankings for 2018, that small numerical difference in RPIs represents the gap between Arizona (0.612; 18th in RPI) and Loyola-Chicago (0.6027; 26th).

 

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¹I calculate this effect by multiplying the estimated coefficient 0.0787 ranks/year by 17 years. Letting this effect vary by type of conference added no explanatory power (p>.75 no difference). A test of whether the slope of the relationship between RPI and seeding varied over time, by including the interaction of RPI and time, was similarly unproductive.  The gap in seedings did not change over time producing the parallel lines in the graph above.

Three teams, Virginia, Xavier and Villanova, have placed themselves quite far ahead of the pack this year.  At the moment, Duke would be favored to win the last remaining top seed, but North Carolina could overtake Duke were UNC to win the ACC championship this weekend.  Winning a major championship is worth about one full rank, which would move North Carolina into the fourth slot and relegate Duke to the second line.  A victory for Clemson in the ACC tournament would move it up to a two seed along with Kansas and North Carolina.

Kansas seems locked into the second line regardless of what happens in the other major conference tourneys.  Michigan’s #11 ranking already incorporates the bonus it received for winning the Big Ten championship last weekend, so it seems unlikely the Committee would move it further ahead of fellow Big Ten member Purdue, based on the latter’s overall season record.

The SEC Tournament could provide some additional drama as well.  Only one of Auburn and Tennessee can win the SEC championship.  That team will likely be placed on the second line, with the other seeded one rank behind.

Only three of these teams, Nevada, Gonzaga and Rhode Island, do not play in a major conference.  Gonzaga’s score includes its “customary” two-seed bonus; it might or might not receive that again this year.  The ACC, Big East, Big Ten, and SEC conferences have roughly equal numbers of teams on this list.  The Big 12 and Pac 12 have just one each.

RPI, Conference Memberships, and Major Championships Determine Seedings

Gonzaga, Cincinnati, and Connecticut have been especially favored.

Selection Sunday for the 2018 NCAA Men’s College Basketball Tournament is just days away.  In past years I’ve published reports on how the Tournament Committee gives an advantage to teams in major and mid-major conferences and grants a seeding bonus to major champions.  Recent conversations with a friend raised the issue of whether the Committee somehow plays favorites by seeding some conferences or teams above or below others after adjusting for objective ability.  This report takes a look at such possible favoritism by the Committee.

As before I am using my database of 1,088 tournament appearances by 241 different basketball programs covering the 2001 through 2017 Tournaments.  The results appear in this companion article.

Once again we see that the Tournament Committee looks more favorably on teams from the major and mid-major conferences.  A team with an 0.60 RPI would be seeded seventh if it plays in a major conference, eighth if it hails from a mid-major, but eleventh if it comes from any other conference.

The Tournament Committee likes to stress that it looks at a team’s whole record when making seeding decisions and does not weight the end-of-season conference tournaments all that highly.  That appears to be true for all the conferences but the six “majors,” the Atlantic Coast, Big 12, Big East, Big Ten, Southeastern and Pac 12 Conferences.  Champions from the major conferences have been seeded an average of one rank higher than other major conference teams with identical RPI scores.

Does the Committee Play Favorites?

Most theories of favoritism are usually based on the assumption than the NCAA and its partners in the television industry have a clear incentive to structure the Tournament to drive ratings.  That creates a pressure to feature marquee teams like Duke or Kansas who will reliably draw a nationwide audience.  In the brutal, single-elimination format of the Tournament, the Committee has strong incentives to seed the most popular teams higher and improve their chances of survival. But is there any other evidence of favoritism when it comes to specific teams or conferences?

I searched for favoritism by comparing the actual seedings awarded a team with the seedings I predict based on RPI, conference membership, and major championships.  I began with the five teams that have appeared in every Tournament since 2000 — Duke, Gonzaga, Kansas, Michigan State and Wisconsin.  Are any of these schools’ impressive unbroken records the result of some bias over the years by the various Tournament Committees, or did these terms earn their ways to the Tournament in the gym?

For all but one of those teams I find no evidence of bias.  The outlier is, perhaps not surprisingly, Gonzaga, the only mid-major in that group of five, and the darling of college basketball fans for years.  By my reckoning, the Tournament Committee has seeded Gonzaga nearly two (1.9) ranks higher than what my model predicts for any other mid-major team with the same RPI score as Gonzaga over the years.  That means Gonzaga should have averaged an eight seed rather than the 6.2 it was awarded over the years.

I expanded my search for team favoritism to all teams with at least twelve appearances to ensure any measured effect was not just because of small sample sizes.  By that criterion only Cincinnati, with twelve appearances over the seventeen years, joined Gonzaga as a favored team.  Cincinnati, like Gonzaga, received a seeding of 6.2 on average; by my estimates they also should have averaged close to eight.

When I look for favoritism by conference, I find only a slight advantage given to the famous Atlantic Coast Conference, and significantly lower seedings given to teams from three mid-majors, the American Athletic, Colonial, and Western Athletic Conferences.  WAC teams are discounted a full seed, and teams from the other two conferences suffer a disadvantage closer to 1.5 seed ranks.

I included a test for Connecticut (with only eleven appearances it was not included above) and find that it, too, was awarded a bonus of about one full seed point.  Unlike Gonzaga and Cincinnati, though, the Tournament Committee’s confidence in UConn has been demonstrated on the floor.  UConn has won the Tournament three times in this period and averaged 2.91 wins per Conference appearance, behind only North Carolina at 3.07.  Since seeding so strongly determines a team’s overall performance, we might wonder whether Connecticut’s impressive record was the result of favoritism.  The other two advantaged teams, Gonzaga and Cincinnati, have not fared especially well on the floor.  Gonzaga has averaged only 1.41 wins per appearance, and Cincinnati just 0.83.