A Brief Intro to the New WBF Scales
by Peter Buchen
March 2014
The new WBF Victory Point (VP) scales were introduced at the 2013 Bali World Teams Championships. These scales were designed specifically for round robin teams matches where every team plays every other team in the tournament. Modifications, which are yet to be fully determined may have to be be applied for Swiss Teams matches, where each team plays only a small subset of the tournament complement. Other adjustments have to be applied for Butler Imped Pairs events, where each pair is Imped against a datum score.
Conversion of Imps to VPs is a necessary requirement in most multi team events. The old scales were discrete and had a number of anomalies. The new scales differ from the old ones in two significant ways. First, the new scales are continuous, so every Imp counts. This removes the “cusp effect†present in the old scales, where some Imps are worth nothing and others a full VP. Second, the Imp margins in the new scale are worth progressively less VPs as the size of a team’s winning margin increases. For example, the extra Imp from winning by a margin of 20 to 21 Imps will be worth less VPs than the extra Imp from 10 to 11 Imps say.
The new continuous VPs are expressed from 0 for a maximum loss to 20 for a maximum win. Intermediate wins are expressed to two decimal places, such as a score of 12.48 VPs for the winner and 7.52 VPs for the loser. The winner’s and loser’s VPs will always add up to 20 VPs. The two decimals are absolutely necessary to ensure the integrity of the mathematics that underlie the construction of the new scales.
For local clubs which prefer to use discrete scales (without decimals) the WBF have also published new versions of these for the commonly used board numbers in play. These, as well as the continuous scales, can be downloaded from the WBF web-site at:
www.worldbridge.org/victory-point-scales.aspx
If you have any queries about the new scales feel free to contact me at: