Rankings Algorithm FAQ

What algorithm is used to calculate the projected rankings?

Our projected rankings are the result of an implementation of the USA Ultimate ("USAU") Top 20 algorithm, which is used to allocate post season bids to both college and club ultimate teams. Learn more about the algorithm here.

TL;DR, here is the rating function: Every game a team plays gets a rating equal to the opponents rating +/- the score value. With all these data points, we iterate team ratings until convergence. There is also a rule for discounting blowout games (see next FAQ).

Excerpt from the USAU Rankings Algorithm

For reference, here is a handy table with frequent game scores and the resulting game value:

Table from the USAU Rankings Algorithm

What is the blowout rule? Is that why some games are marked 'Ignored?' (Spoiler: Yes)

"...if a team is rated more than 600 points higher than its opponent, and wins with a score that is more than twice the losing score plus one, the game is ignored for ratings purposes. However, this is only done if the winning team has at least N other results that are not being ignored, where N=5."

Translation: if a team plays a game where even earning the max point win would hurt them, they can have the game ignored provided they win by enough and have suffficient unignored results.

For a more in-depth explanation of how blowouts affect the algorithm, check out our Blowout Rule explainer.