The RPI formula is a well-established method to rank sports teams. It is used by college baseball and other NCAA sports to provide an objective ranking system based on a team's winning percentage and it's strength of schedule.

A team's RPI ranking is calculated based on three factors:

1. Their winning percentage (25% of ranking)
2. Their opponents' winning percentages (50% of ranking)
3. Their opponents' opponents' winning percentages (25% of ranking)

These winning percentages are combined for a weighted aggregate score. Teams are then ordered by their score to come up with the final rankings.

The Strength of Schedule (SOS) for a team is calculated as 2/3 opponents' winning percentage + 1/3 opponents' opponents' winning percentage.
Travel Ball RPI Adjustments
Travel Ball RPI makes a few adjustments to the college RPI formula to provide a more accurate ranking of youth baseball teams.

1. Minimum opponents & games - teams must have played at least 5 different opponents and at least 10 games total. If a team has not reached these minimums, they will not be included in this week's rankings.

2. Playing different age groups - when teams play up an age or down, there is a multiplier for those games.
- A win or loss within age group counts as 1.
- A win against an older team counts as 1.2 wins.
- A loss against an older team counts as 0.8 losses.
- A win against a younger team counts as 0.8 wins.
- A loss against a younger team counts as 1.2 losses.

In short, wins against older teams help out your RPI more. Losses against younger teams hurt your RPI more.
Travel Ball RPI is a mathematical way to rank travel baseball teams. There is no subjective assessment of teams, nor does it rank teams based on their "ability". The ranking is solely based on if they win or loss games and if their opponents win or lose their games. While there is bound to be disagreement with the rankings, it's really just math.
Frequently asked questions
Q. Why did a team move up (or down) in the rankings even if they didn't play last weekend?

A. The rankings are a combination of both a team's winning percentage and their opponents' winning percentage. If a team's opponents win (or lose) games during a weekend, their RPI ranking may change even if they did not play.

Q. Why is a team not ranked?

A. Generally, if a team is not ranked it is because they have not played enough games or enough different opponents for a RPI ranking to be calculated. Once they play enough opponents, they will be automatically included.

Q. Does Travel Ball RPI only use games against other opponents from the same state in the rankings?

A. No! Travel Ball RPI counts all of a team's games and analyzes all of a team's opponents in calculating their RPI ranking.

Q. If we play a team more than once in a season, how does that impact the rankings?

A. Your opponent will be counted multiple times in the Strength of Schedule component of the rankings. If you play a good team more than once, it will improve your SOS.

Q. How often will rankings be updated?

A. The first ranking for a season will generally come out 3-4 weeks into the season once we have enough data. After that, rankings will be updated weekly on Mondays.

Q. I have feedback or a question. Who can I contact?

A. Please feel free to reach out to travelballrpi@gmail.com