How well does each ranking system predict tournament results? We want to know. We need to know how and where to improve our own ranking system — BennettRank — so we need the answer to this question.
You tell us every year in our post season surveys the Coaches Poll has the most credibility. If we want to "be the best" we need to "play the best." As such, we do a post season post-mortem as to how well does BennettRank perform vs. the Coaches Poll.
The results are in for the 2016 NCAA Volleyball season:
BennettRank 2, Coaches Poll 1
(D1, D2, and D3)
How did we do our analysis? We took the average ranks of all teams at each stage of the tournament from the Field of 16 to the Championship game and compared results.
For each division, the results are shown in separate sections. This analysis is based on the final pre-tournament rankings by BennettRank and the Coaches Polls.
D1 Volleyball: BennettRank
The eventual D1 volleyball national champion, Stanford, was ranked #5 by BennettRank and #12 by the Coaches Poll going into the tournament. The runner-up, Texas, was ranked #4 and #5 respectively. The win by BennettRank can primarily be attributed to Stanford, who helped all stages of the analysis.
BennettRank won all four of the four stages; with better average ranks in the field of 16, the quarterfinals, the semifinals, and the championship game. We discount the field of 16 results since we see bias on the selection committees to choose top 25 coaches poll teams systematically in almost every division. There were four top 25 BennettRank teams that did not make it into the field of 16 and only three for the Coaches Poll. [divider]
D2 Volleyball: BennettRank
All things considered though, BennettRank performed better in all four stages. The championship squared off teams ranked 1 and 6 for BennettRank, and 1 and 9 for the Coaches Poll.
D3 Volleyball: Coaches Poll
Washington University came out of the blue to win the championship game. Both polls had them in the teens coming into the tournament.
Across the board, the coaches poll did a little bit better, narrowly winning three of the four stages.
Some conclusions from this overall analysis:
1. BennettRank was better this year in predicting volleyball tournament results than the coaches polls. From other analysis, we believe the coaches and tournament selection committees emphasize wins and overall record; discounting strength of schedule. BennettRank includes margin of victory and strength of schedule in its algorithms.
2. Some coaches poll committees do better than others. Kudos to the D3 volleyball coaches for out-doing BennettRank this fall. The football coaches poll committees also do a pretty good job, compared to the poll committees of other NCAA sports and divisions.
3. We were surprised at how well both BennettRank and the Coaches Poll did in D2. D2 consistently is the most problematic for us because of the regional nature of its polling and tournament selection.