Round Robin Tally Policy

A Tally Policy controls how order is determined for Round Robin groups.

See engine.attachPolicies.

const roundRobinTally = {
  groupOrderKey: 'matchUpsWon', // possible to group by tieMatchUpsWon, tieSinglesWon, tieDoublesWon, matchUpsWon, pointsWon, gamesWon, setsWon, gamesPct, setsPct, pointsPct, matchUpsPct
  groupTotalSetsPlayed: false, // optional - when true will calculate % of sets won based on total group sets played rather than participant sets played
  headToHead: { disabled: false },
  tallyDirectives: [
    // these are the default values if no tallyDirectives provided; edit to suit
    // idsFilter scopes the tally calculations to only tied participants
    // with { idsFilter: false } the ratio is calculated from all group matchUps
    // with { idsFilter: true } the ratio is calculated from matchUps including tied participants
    // when { maxParticipants: 2 } is defined, the rule only applies when # of participants is <= maxParticipants
    // any attribute/idsFilter combination can be selectively disabled for Head to Head calculations
    { attribute: 'matchUpsPct', idsFilter: false, disbleHeadToHead: false },
    {
      attribute: 'tieMatchUpsPct',
      idsFilter: false,
      disbleHeadToHead: false,
    },
    { attribute: 'setsPct', idsFilter: false, disbleHeadToHead: false },
    { attribute: 'gamesPct', idsFilter: false, disbleHeadToHead: false },
    { attribute: 'pointsPct', idsFilter: false, disbleHeadToHead: false },
    { attribute: 'matchUpsPct', idsFilter: true, disbleHeadToHead: false },
    { attribute: 'tieMatchUpsPct', idsFilter: true, disbleHeadToHead: false },
    { attribute: 'setsPct', idsFilter: true, disbleHeadToHead: false },
    { attribute: 'gamesPct', idsFilter: true, disbleHeadToHead: false },
    { attribute: 'pointsPct', idsFilter: true, disbleHeadToHead: false },
  ],
  excludeMatchUpStatuses: [], // matchUpStatuses to exclude from calculations, e.g. ABANDONED, INCOMPLETE
  setsCreditForDefaults: false, // whether or not to award e.g. 2 sets won for participant who wins by opponent DEFAULT
  setsCreditForWalkovers: false, // whether or not to award e.g. 2 sets won for participant who wins by opponent WALKOVER
  setsCreditForRetirements: false, // whether or not to award e.g. 2 sets won for participant who wins by opponent RETIREMENT
  gamesCreditForDefaults: false, // whether or not to award e.g. 12 games won for participant who wins by opponent DEFAULT
  gamesCreditForWalkovers: false, // whether or not to award e.g. 12 games won for participant who wins by opponent WALKOVER
  gamesCreditForRetirements: false, // whether or not to award e.g. 2 sets won for participant who wins by opponent RETIREMENT
  gamesCreditForTiebreakSets: true, // defaults to true; whether to count a tiebreak set as a game won, e.g. 6-2 2-6 [10-3]
  GEMscore: ['matchUpsPct', 'tieMatchUpsPct', 'setsPct', 'gamesPct', 'pointsPct'],
};

engine.attachPolicies({ policyDefinitions: { roundRobinTally } });

Default Behavior

Round Robin group tally logic by default implements the following guidelines:

1. The participant who wins the most matches is the winner.
2. If two players are tied, then the winner of their head-to-head match is the winner.

If three or more participants are tied, tie are broken as follows:

• The head-to-head win-loss record in matches involving just the tied players;
• The participant with the highest percentage of sets won of all sets completed;
• The head-to-head win-loss record in matches involving the players who remain tied;
• The participant with the highest percentage of games won of all games completed;
• The head-to-head win-loss record in matches involving the players who remain tied;
• The participant with the highest percentage of sets won of sets completed among players in the group under consideration;
• The head-to-head win-loss record in matches involving the players who remain tied;
• The participant with the highest percentage of games won of games completed among the players under consideration; and
• The head-to-head win-loss record in matches involving the players who remain tied.

Implementation Details

After initial separation of participants by matchUpsWon, the implementation is configurable by supplying an array of tallyDirectives in the Tally Policy.

The algorithm relies on the values availble in the calculated participantResults and works as follows:

• separate participants into groups by a given attribute
• a group with a single participant is 'resolved'
• groups of two participants are resolved by head-to-head (if not disabled/if participants faced each other)
• groups of three or more search for an attribute that will separate them into smaller groups
• participantResults scoped to the members of a group and recalculated when { idsFilter: true }