Backgammon Club Leuven

By Leuven's 4 Cubes captain Toon Van Herreweghen

In our club meeting on January 14 (report), it has been said that participation in the 4 Cubes collisions would be based on rating AND club championship points (CP), with progressive weight of the latter.

Core principle is: we start with Rating, and on 31/12/2011, it will be 100% CP that matters.

Here is how it will be done.

1. Normalisation:

In order for both systems to be combined in a meaningful way, we transform them to a comparable order of magnitude. We will map both of the actual ranges (min, max) in linear fashion to the (0, 100) interval.

2. Weigted average:

D/365, with D the current day number in the year, will be taken as the progressively growing weight of the CP system in the final outcome.

Example:

1. Today, 2/2/2011, Patrick has rating 1603.12 and CP 50.
2. The ratings have currently: min = 1338.96 and max = 1681.67 (a range of 342.71). Patrick's "normalised rating" is: (rating - min) * 100 / range = (1603.12 - 1338.96) * 100 / 342.71 = 77.08.
3. The CP system currently has: min = 0 and max = 50 (range is 50). Patrick's "normalised CP" is: (50 - 0) * 100 / 50 = 100.
4. It is the 33rd day of the year, so CP has weight 33/365 = 9.04% and Rating has 90.96%.
5. So Patrick's combined 4CQ is: 0.9096 * 77.08 + 0.0904 * 100 = 79.15.

A complete and up-to-date 4CQ list will be communicated at the moment that it matters, i.e. on the very day when volunteers are effectively asked if they are willing and able to help oppose a challenging/challenged club in battle (and will remain unchanged and relevant until the specific encounter for which it was generated - read: I will not re-calculate every single day, or estimate the future...)

As an example, for the curious, today a top-10 would look as follows (but by nature it changes every day):

Player                 4CQ
--------------------------
Johan Segers         95.66
Toon Van Herreweghen 89.74
Patrick De Wilde     79.15
Alain Chif           75.05
Zsolt Tasnadi        63.37
Marc Van Haverbeke   61.08
Guy Van Middelem     55.36
Henri Pollet         55.14
Elif Memis           52.30