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VBV Rating System
Why Have A Rating System?
The VBV rating system provides an objective assessment of player ability based on past performance in VBV tournaments. The ratings are used as a guideline to place players of comparable abilities within the same division for each tournament. This helps ensure competitive play and an enjoyable tournament for players in all divisions.
Dependent upon the turnout for a particular tournament, we reserve the right to move a player to a higher or lower division to complete the field for one or more divisions.
New Formula for VBV Ratings for the 2008 Season
For the 2008, VBV is modifying its formula for player ratings to account for rally scoring. The previous formula was established for side-out scoring, where only the serving team can score points. In rally scoring, a player typically scores a higher percentage of possible points - even in a loss - than in side-out scoring.
Why We Are Changing the Ratings Formula
To understand the need to update our ratings formula to account for rally scoring, consider the following example: If Team A beats Team B 11-3 in a side-out scoring game, Team B will have scored 3/11 = 27% of the possible points. In this same game, Team A might have beaten Team B 21-13 in rally scoring. In this case, Team B would have scored 13/21 = 62% of the possible rally scoring points. The effect of rally scoring ÒinflatesÓ Team BÕs percentage by 35 points over what they would have received in side-out scoring. This rally scoring ÒinflationÓ creates an uneven distribution of ratings based on points alone, and the new VBV ratings system attempts to address this issue.
The New VBV Rally Scoring Ratings Formula
The new VBV ratings formula will be based on a weighted combination of 75% points won and 25% games won. The best way to describe the new formula is with an example: Assume a player plays 6 rally scoring games to 21, wins 4 games and scores 105 of the possible 126 points. This player therefore wins 67% (4 out of 6) of games played and 83% (105 out of 126) of the possible points. The unadjusted rating for this player will be: (75)x(0.83) + (25)x(0.67) = 79.2
As with the previous ratings formula, if you are undefeated in your pool - winning 100% of games played and 100% of possible points - your unadjusted rating will be 100.
The unadjusted score above will then be adjusted by a weighting factor for each division. These weightings have also been revised for 2008 to account for rally scoring. The new weightings are listed below and applied to the sample calculation above:
Division Weight Factor Example Division 1 1.0 79.2 x 1.0 = 79.2 Rating Division 2 0.8 79.2 x 0.8 = 63.3 Rating Division 3 0.6 79.2 x 0.6 = 47.5 Rating Division 4 0.4 79.2 x 0.4 = 31.7 Rating Bonus points are awarded for the playoffs for each division. If you earn a playoff spot and play in the playoffs, you will get an extra 0.5 bonus points added to your final adjusted rating for that tournament. If you come in 2nd place in your division, you will receive 1.0 bonus points, and if you place 1st overall, you will receive 2.0 bonus points.
A player's final rating is then determined by the average rating over the last 10 VBV events in which the player participated (excluding Mixed 4's). This averaging helps minimize the impact of a Òbad dayÓ on the playerÕs rating, but will also allow the player to advance to a higher division with consistently high scores.
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