Chapel Hill, North Carolina – The NC High School Athletic Association released the first RPI odds of the season for soccer, volleyball and men’s football on Tuesday morning.
This is the first time that RPI odds will be used by the NCHSAA for purposes of sowing the state playoffs. The association has used MaxPreps’ potency rankings in the past, but some people have expressed concern about the lack of transparency behind the MaxPreps formula.
RPI odds use a simple formula that takes into account a team’s win percentage, a team’s opponent win percentage, and a team’s opponent win percentage. The formula is: RPI = (0.3 x WP) + (0.4 x OWP) + (0.3 x OOWP).
An opponent’s win percentage is calculated using the opponents’ average win percentage, not using a combined record. All matches involving the team whose RPI is calculated are omitted from the average.
There are differences for opponents outside the state. For teams from Georgia, South Carolina, Tennessee and Virginia – states bordering North Carolina – RPI odds will be calculated the same as NCHSAA opponents in the state, provided they have a MaxPreps account and schedule. For other out-of-state opponents, their direct win percentage will be used, but their opponents will be given a 0.500 win percentage.
Non-NCHSAA State opponents will be treated as a non-border State team.
International opponents do not count for the RPI ranking.
The playoff process will be different this year from previous seasons. Each conference will be assigned a certain number of automatic seats based on the number of schools participating in a conference participating in a particular sport. In conferences with 1 to 5 teams, the conference champion will qualify. In conferences with six or more teams, the conference champion and the second place team (or the conference tournament champion) will qualify.
In a split conference, the highest ranked team in a ranking will automatically qualify, regardless of the overall conference ranking, provided there are at least two schools of a given ranking in the conference.
Schools have already been assigned to the eastern or western regions. Everything from Caswell, Alamance, Chatham, Moore and Richmond counties to the east is in the Eastern region, while everyone west of this line is to the west. Each region will fill the remaining spots in the playoff field with overall teams based on their RPI scores.
For ranking purposes, conference champions will be ranked first by RPI ratings. All other schools will then be ranked according to their RPI score, regardless of the end of the conference. Each region will be seeded independently of each other.
Football, soccer and volleyball will all feature groups of 64 teams in each classification with 32 teams coming from each region.