Updated January 2015



This website is a resource for Division I college women's soccer coaches and fans and has four purposes:

1.  One purpose is to provide information on what the Ratings Percentage Index (RPI) is, as used for Division I women's soccer.  This includes providing information on how the NCAA uses the RPI in making at large selections, in seeding, and in placing teams in the bracket for the NCAA Tournament.

2.  The second purpose is to provide Division I women's soccer teams' detailed RPI ratings and RPI-based information over the course of each NCAA season.  This allows coaches and fans to see how their teams are doing in the RPI rating process, to see how teams' RPI ratings evolve over the course of the season, and to better understand how the RPI works in real life.  RPI ratings current through the previous Sunday's games appear on the "RPI REPORTS" page by Tuesday each week, once the season has gotten through its first three or four weeks.  In addition, RPI end-of-regular-season reports for previous years are available on the "Reports Archive" page.

3.  The third purpose is to evaluate how well the RPI measures teams' performance.  This includes evaluating the different versions of the RPI as the Women's Soccer Committee has changed it over time and trying to get a sense of what the Committee's purpose has been in making the changes.  It also includes identifying changes that might improve the RPI's performance.

4.  The fourth purpose is to provide information on the rules that govern the NCAA Women's Soccer Committee's at large selection, seeding, and bracket formation for the NCAA Tournament; to suggest guidelines for those who want to predict what decisions the Committee will make this year; and to provide a system for making at large selections and seeds that comes very close to matching the Committee's decisions, particularly for at large selections, and that also provides a means for analyzing the Committee's decisions from year to year.  It also includes providing information to coaches for use in scheduling with a view to maximizing their teams' chances of getting NCAA Tournament at large selections and seeds.


Your questions, comments, and criticisms will help improve this website.  I've done some major research projects in response to questions and comments I've received on the Blog page.  Simply click on "BLOG: Ask Your Questions, Give Your Comments, Please" in the menu to the left of this page, enter an on-line name and whatever you want to say in the "Comments" form, and click "Submit."  When you refresh your browser, your post should appear below the Comments form.  The way this works on Google Sites, initially you'll have to scroll down to the bottom of the comments page to see what you've entered.  I regularly visit this page and manually reverse the order of the entries so that the most recent is at the top.  I apologize for the way that works, but it's the best I can do.


I've tried to arrange the webpages in a logical order.  Here's a brief description of each page (other than this "Home" page and the "Blog" page):

"Getting the Correct Data":  This page describes how the NCAA gathers game data, potential problems in data gathering, and actual data gathering problems the NCAA has had in recent years.

"RPI: Formula":  This page shows how the NCAA computes the RPI for Division I women's soccer.  It also shows the changes the NCAA Division I women's Soccer Committee has made in the RPI formula during the period beginning with the 2007 season.

"RPI: Measuring the Correlation Between Teams' Performance and Their Ratings":  This page describes a system I have developed for measuring how teams in different groups perform in relation to their ratings.  I refer to these measurements in a number of the other pages.

"RPI: Non-Conference RPI":  This page shows how the NCAA computes the Non-Conference RPI and provides information about the NCAA's rationale for using the NCRPI.  It also discusses the problem the RPI has fairly rating teams from different conferences in relation to each other.

"RPI: Regional Issues":  This page discusses the problem the RPI has fairly rating teams from different regions in relation to each other.

"RPI: Effect of the 2012 Bonus/Penalty Change":  In 2012, the Women's Soccer Committee changed the bonus/penalty adjustment formula for the Adjusted RPI.  This page discusses the effects of the change from an RPI and NCAA Tournament perspective.

"RPI: Element 2 Issues":  This page discusses issues related to how the NCAA computes Element 2 (part of "strength of schedule") of the RPI.  It also discusses a modified way of computing Element 2 as a possible future change to the RPI formula.

"RPI: Home/Away/Neutral Issues":  This page discusses issues related to home, neutral, and away game locations and the RPI.

"RPI: Modified RPI?":  This page discusses possible modifications to the RPI, specifically my "Improved" ARPI and my "Iteration 5 URPI.".

"RPI: Effect of Conference Tournaments":  This page discusses the question whether it is advantageous or disadvantageous, for RPI purposes, for conferences to have end-of-season tournaments.

"RPI: Strong, Large Conferences":  This page discussions the question whether strong, large conferences should play full conference round robins or not.

"NCAA Tournament: Selection, Seeding, and Bracketing Criteria":  This page explains the NCAA rules that apply to the selection of teams to participate in the NCAA Tournament, the seeding of teams in the Tournament, and the placement of teams within the bracket.

"NCAA Tournament: Bracket Procedure":  This page explains the procedural steps that the NCAA staff and the Division I Women's Soccer Committee go through in formation of the NCAA Tournament bracket.

"NCAA Tournament: Predicting the Bracket, Interim Ranking Reports":  This page provides resource information for those interested in trying to predict who will be candidates for at large selections and seeds for the NCAA Tournament.

"NCAA Tournament: Predicting the Bracket, At Large Selections":  This page describes my system -- automated, computer driven, and based on the applicable NCAA criteria -- for making at large selections for the NCAA Tournament.  It includes comparisons of my selections to the Women's Soccer Committee's and, for the few differences, discusses the differences.

"NCAA Tournament: Predicting the Bracket, Seeding":  This page shows how my system, described on the "... At Large Selections" page, seeds teams.  It compares my seeds to the Women's Soccer Committee's and discusses the differences.

"NCAA Tournament: Scheduling Towards the Tournament":  This page is intended as a resource for coaches in setting schedules with a view towards getting an at large selection for, or a seed in, the NCAA Tournament.  It includes a link to, and information on, an excellent scheduling resource at the nc-soccer website.

"RPI: THIS YEAR'S REPORTS":  This page contains the weekly RPI reports for the current season and, when appropriate, my comments if a report provides a good illustration of a particular aspect of the RPI.

"RPI: Reports Archive":  This page contains an archive of RPI reports for previous years.


To print a page from this website, click on the "Print Page" command at the bottom of the page.  This will take you to a printable version of the page.  Then use the "Print" command in your "File" menu to print the page.


My name is Chris Thomas.  I am a retired attorney who is a nearly life-long soccer fan.  I played high school and college soccer in the late 1950s and early 1960s and have played adult soccer occasionally since then.  I live in Portland, Oregon and am a University of Portland women's soccer fan and a fan of the NWSL's Portland Thorns.  I was head coach of the St. Mary's Academy (Portland, OR) girls tennis team for 19 years, ending with the 2014 season, and have coached U8 through U10 girls rec soccer and futsal teams, manage a competitive girls U11 team, and coach a competitive girls U11 futsal team.  I have a US Soccer Federation "E" license.

I began studying the RPI and how the NCAA uses it for Division I women's soccer in 2006, in an attempt to understand why the Women's Soccer Committee did not select the University of Oregon to participate as an at large selection in the NCAA Tournament, notwithstanding its having finished second in the then Pac 10 Conference.  I "cloned" the RPI at the beginning of the 2007 season using Excel and have done RPI calculations for Division I women's soccer over the course of the 2007-2014 seasons.  I also have done studies on the Women's Soccer Committee's decision making process on seeds and at large selections for the NCAA Tournament, as well as on how teams desiring at large selections and seeds in the Tournament might schedule with a view to maximizing their chances for a seed or at large selection.

I do my RPI work to support women's soccer, to have fun, and to help build understanding, within the Division I women's soccer coaching and fan community, of the RPI and of the Women's Soccer Committee's decision-making process.  As part of my support for women's soccer, one of my objectives is to provide for the Division I women's soccer community an RPI information resource that is at least as good as any RPI resource available for other sports, including for men's sports.  I believe this website meets that objective.

My approach is to try to provide clear, accurate, and unbiased information about the RPI and how the NCAA uses it, as related to Division I women's soccer.  When I want to express my own opinion about the RPI, I try to be clear that is what I am doing.  My objective is to provide information in a way that will help readers form their own independent, well-grounded understandings of and opinions about the RPI:  I would rather give coaches and fans the tools they need to answer their RPI questions than have them look to me for answers.  Thus although I field and answer questions from coaches and fans, in my answers I try to lay out the process I went through in arriving at the answers so that in the future, if possible, the question askers will have the tools to answer their questions themselves. There also is some information about the RPI and how the NCAA uses it that I believe to be true but cannot absolutely verify.  When I provide that information, I try to remember to include appropriate disclaimers so readers will be able to make their own judgments about its reliability.