The NFCA, in conjunction with mathematician Warren Nolan, is once again releasing a ratings percentage index (RPI) for Division I softball. The first rating was released on Friday, March 28.
2008 NFCA Simulated Ratings Percentage Index
Florida sits atop the first release of the NFCA RPI for 2008. The Gators have a 35-2 record through Sunday, March 23, which is the most recent data included in the RPI. UF is currently ranked third in the USA Today/NFCA poll and the Gators hold a slim advantage in the RPI over No. 2 Alabama. No. 20 Long Beach State holds the nation’s toughest strength of schedule thus far and is ranked sixth in the inaugural RPI for 2008.
The NFCA RPI is scheduled to be released weekly through the selection of the NCAA Tournament field, which will be announced on Sunday, May 11.
What is the RPI?
The RPI is a mathematical calculation used to help determine each team’s success, using a calculated strength of schedule and won-loss percentage.
The NCAA developed an RPI for several sports in order to give each of its selection committees an additional tool for selecting NCAA championship fields. Historically, the NCAA RPI has not been released until the conclusion of the respective seasons.
In a change from that practice, the NCAA is scheduled to release its 2008 Division I softball RPI on April 4, April 18 and May 2. It is anticipated that it will be slightly different from the NFCA’s RPI because the NCAA employs a system of bonus and penalty points that are not released to the public.
“We first developed the RPI in the 2005 season as a benefit for our members,” said NFCA Executive Director Lacy Lee Baker. “Since the NCAA did not release its RPI, we wanted to provide our own mathematical calculation so Division I coaches could get an idea of team standings as the season progressed. Although a coach couldn’t change his or her schedule mid-season, he or she knew the importance of an upcoming game.
“Although the NCAA will release an RPI this year during the season, we think the NFCA weekly compilation is still interesting and helpful. From reports we’ve received from the softball community, it’s apparent that coaches and fans agree,” Baker continued.
The NFCA RPI is also available as a tool to the 30 coaches who vote for the USA Today/NFCA Division I Top 25 poll, as well as the coaches and committee selecting the Louisville Slugger/NFCA All-Region and All-America teams.
The NFCA RPI utilizes a formula that is based on the one used for Division I men’s and women’s basketball. There are minute differences in the penalties and bonuses that are specific to each sport. For example, there may be a small penalty for a Division I school that plays a non-Division I opponent and there may be a small bonus for beating a team that is ranked in the USA Today/NFCA Top 25 poll.
When determining the RPI for each team, the following basic formula is used for both the NFCA and NCAA RPI:
25% -- Winning percentage.
50% -- Opponents’ winning percentage.
25% -- Opponents’ opponents’ winning percentage.
Although the NCAA publishes this basic formula, it does not release the mathematical bonuses and penalties specific for each sport. It is important to note that the NFCA RPI will not be exactly the same as the NCAA RPI, since the NCAA does not release its bonus and penalty calculations. However, the two should be close and the NFCA RPI should be an indication of where a team stands. The NCAA does not endorse the NFCA RPI.
What are the procedures used in developing the NFCA RPI?
To prepare an RPI, the mathematician must have every score in the nation. All of the 30 conferences that sponsor Division I softball have assisted in this process by sending their statistical “XML” files to the NFCA. This file is prepared each week and submitted both to the NFCA for RPI purposes and to the NCAA in order to generate national statistics and the NCAA RPI. The XML file is created through the Stat Crew software “The Automated Scorebook for Baseball/Softball”
Scores for Division I independent teams are collected either through XML files or are gathered by the NFCA staff and sent to the mathematician.
The NFCA has selected Nolan, a mathematician who is involved in calculations for football’s Bowl Championship Series, to calculate the RPI. He also publishes his own basketball and baseball RPI.
Nolan receives the XML files and other scores by Wednesday. After the information is proofed and corrected by the NFCA, the RPI is published weekly on NFCA.org.