# DI Rankings 11/14/16

What is the difference between a “poll” and a “ranking” when applied to sports teams? A poll, sometimes known as a rating, involves an opinion of the team’s performances by people who are knowledgeable about both the sport involved and the teams in question. Hence a poll is a vote and a subsequent ordering of teams based upon this vote. A ranking usually involves a mathematical calculation based on the performances of the teams in question and the performances of their opponents. Therefore, a ranking is a statistical concept which evaluates the performances of teams. In general, polls and rankings complement each other because each represents a different viewpoint and a different “skill set” in terms of evaluating volleyball.

The Net Set Ranking is a numerical average based upon the performances of teams in four other polls or rankings. In the Net Set Ranking, the team’s position in each of the four polls is summed and then averaged to create a Net Set Index. This net Set Index is then arranged, or ranked, in ascending order, with the lowest Net Set Index determining the number 1 team in the Net Set Ranking, and so forth. By combining polls and rankings into a single index number, we obtain both the mathematical benefits of the rankings and the human performance insights of the coaches from the polls. Net Set Rankings and the Net Set Index are an average from these four polls or rankings.

1. The AVCA Coaches Poll, 11/14/16 (https://www.avca.org/polls/di-women/index.html).

AVCA, or the American Volleyball Coaches Association, publishes an outstanding weekly poll for each volleyball division from its member coaches in that division. Thus, DI coaches are voting on the teams in the DI poll.

2. The Rich Kern Poll, 11/14/16 (http://www.richkern.com/vb/FreePage.asp).

Richkern.com has a free portion and a much larger premium service. The premium service is well worth the modest subscription fee of \$25.00 annually. This poll has been around for a long time and the pollsters are journalists and volleyball fans who really know their stuff. To see the Rich Kern Poll intact, and lots of other neat volleyball stuff, go to: (http://www.richkern.com/vb/rankings/FreePageRankings.asp).

3. The Pablo Rankings, 11/14/16 (http://www.richkern.com/vb/FreePage.asp).

The Pablo Rankings are an incredibly ingenious ranking system that operates on a probabilistic, algorithmic approach and analyzes and measures the difference in abilities between two teams overall and in a match. In terms of accuracy and predictive analytics, the Pablo Rankings are the most accurate mathematical model available today. You can find a detailed explanation of the Pablo Rankings at this web location.

http://www.richkern.com/vb/rankings/PabloFAQ.asp . View the Pablo Rankings, the best pure statistical ranking available, at RichKern.com:

4. The NCAA RPI Index, 11/14/16 (http://www.ncaa.com/rankings/volleyball-women/d1/).

The RPI ranking is one of the discriminators for determining the at-large bids to the National Championship Tournament. Here is the basic formula for the RPI rankings currently used by the NCAA. Please note that several variations of this formula exist, but the one below is the basic formula.

RPI = (Winning %*.25) + (Opponent’s Winning %*.50) + (Opponent’s Opponents Winning *.25)

(Winning % is calculated by dividing team’s wins by the number of games played.)

As you can see from this formula above, 75% of the RPI comes from how a team’s opponents performed (aka Strength of Schedule), while only 25% of the RPI is based on the team’s actual performance. Quite frankly, that isn’t correct, statistically or logically. Nonetheless, it is used by the NCAA for seeding and at-large bids. To see the all NCAA Division I RPI Index rankings, go to this web location:(http://www.ncaa.com/rankings/volleyball-women/d1/ncaa-womens-volleyball-rpi).

Before we move on to this week’s rankings, though, I have to comment on the NCAA RPI Index for 11/14/16. Last week Texas was number 2 in the RPI Index. This week they lost to Baylor, a good but still unrated team, and yet Texas somehow improved in the RPI to Number 1! The previous number 1, Wisconsin, which won both of its matches, was displaced by both Texas and Nebraska, which also won both of its matches. Wisconsin somehow dropped to number 3 in the RPI. Someone has to explain that movement to me because it makes no sense logically or statistically.

 Net Set # School Conference 2016 W-L NS Index AVCA Poll RichKern Poll NCAA RPI Pablo Rank 1 Nebraska Big 10 24-1 1.25 1 1 2 1 2 Minnesota Big 10 21-4 2.50 2 2 4 2 3 Wisconsin Big 10 22-3 3.50 3 3 3 5 4 Florida SEC 25-2 4.25 5 4 5 3 5 Texas Big 12 19-4 5.75 7 6 1 9 6 BYU WCC 24-3 7.50 10 7 6 7 7 Kansas Big 12 23-2 7.75 4 5 10 12 8 Stanford Pac 12 17-7 8.75 12 10 7 6 9 UCLA Pac 12 21-5 9.50 9 9 12 8 10 Washington Pac 12 22-4 9.75 8 8 13 10 11 San Diego WCC 22-4 11.25 11 11 8 15 T12 Michigan State Big 10 23-5 13.00 13 14 11 14 T12 North Carolina ACC 23-3 13.00 6 13 8 25 14 Penn State Big 10 19-8 14.00 15 12 25 4 15 Michigan Big 10 21-7 17.25 18 16 15 20 16 Oregon Pac 12 18-7 18.00 19 17 20 16 17 Utah Pac 12 19-8 18.25 16 18 22 17 18 Creighton Big East 22-6 18.50 21 25 17 11 19 Hawaii Big West 20-5 19.50 14 15 36 13 20 Kentucky SEC 20-6 22.25 23 30 18 18 21 Purdue Big 10 16-11 23.00 30 20 21 21 T22 Missouri SEC 21-5 24.25 25 29 14 29 T22 Ohio State Big 10 17-11 24.25 24 23 29 21 24 Florida State ACC 20-5 24.75 17 19 27 36 25 Western Kentucky C-USA 27-2 25.00 20 26 16 38

LET’S GROW VOLLEYBALL!