Rodney's Ranking Index was developed by Rodney Jacobson for use by USA Ultimate (formerly the UPA) in their tournament score reporter. It is based on college hockey's KRACH algorithm.

With the RRI system, ratings are re-calculated on a daily basis, taking into account the strength of each team's schedule. For example, if your first game was a loss to a low-ranked team who later prove themselves to have been initially under-estimated, the penalty for that loss will be reduced as the season progresses.

USA Ultimate is no longer using RRI as of 2014.

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