Appendix G: Notes on the USCF Swiss Implemented in Vega
Vega implements all the USCF rules (USCF Official Rules - 5th edition 2003). However the user
should be aware of the default behaviour of the program.
1. The colors in a series by default are treated by the variation 29E5f1 that states:
29E5f1: Last-round exception. Except for the last round, when it may be necessary to
pair the tournament or class leaders, players shall not be assigned the same color in
three successive rounds.
This case is the default and Vega handles it automatically. This variation is currently included in all
FIDE Swiss systems. If the tournament director needs for some reason to permit three colors in a
row before the last round, then he should press the checkbox “Accept WWW/BBB” in the pairing
page. To remove the variation 29E5f1 the box “Accept WWW/BBB” should be checked for the
entire duration of the tournament.
At the end of the natural pairing Vega improves the colors using the “Look Ahead method”. Vega
saves in the text file colorlogN.txt (N is the current round) all the switches made during the
application of the look ahead method. The following are typical messages referred to the natural
pairing:
...
Done Transposition between pairs 1, 4
[1] R80 = 0, R200 = 1: D_trans = 54, D_inter_1 = 442, D_inter_0 = 73
Done Interchange between pairs 2, 8
[4] R80 = 0, R200 = 1: D_trans = 124, D_inter_1 = 59, D_inter_0 = 343
...
The meaning is:
R80: is 1 if can be applied the 80 point rule, otherwise is 0;
R200: is 1 if can be applied the 200 point rule, otherwise is 0;
D_trans: rating difference of the transposition between the pairs;
D_inter_1: rating difference of the interchange A<=>D, in the pairs A-B and C-D; D_inter_0: rating
difference of the interchange B<=>C, in the pairs A-B and C-D.
2. The unrated players in Vega are the players with rating exactly equal to 0. The unrated are treated
differently by the USCF rules with respect to the BYE and the odd player determination. All the
players with rating greater than 0 are instead treated in the same way by Vega. Thus, if the
Tournament Director prefers to give to the unrated players the highest priority to be the odd player,
the TD should simply assign to them a minimum rating different from zero, for example 1.
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