Appendix Q: Swiss System with Progressive Acceleration
Objective: This variant of the Swiss system aims to better match opponents of approximately equal
strength during an open tournament. The goal is to allow international norms during an open
tournament where less than half of the players have a FIDE rating.
Principles of operation: When pairing at the start of the round, each player has a global score
(GS), which is equal to the real score gained by play (RS) plus a fictitious score (FS) between 0 and
2:
GS = RS + FS
Rather than relying solely on fixed full-point fictitious offsets to separate the groups, this system
awards additional half-points based on achievement during the tournament. This allows the groups
to merge together more gradually.
Calculation of the fictitious score
Players are divided in 3 groups A, B, C on the basis of their Elo rating. Each group includes a
minimum of 25% and a maximum of 50% of all players. Elo rating is used to limit the groups,
which are decided by the arbiter before the start of first round. The groups may be set according to
the prizes determined by the organizers. In general, group A includes players having an Elo rating
greater or equal to 2000 points and group C includes players with an Elo rating of less than 1600
points.
Like the standard accelerated system, at the start of the tournament, players in group A have two
fictitious points (FS = 2), group B one fictitious point (FS = 1) and group C no fictitious points (FS
= 0).
When a player of either group B or C gains at least 1.5 real points (RS ≥ 1.5), their fictitious score is
increased a further half-point. When a player gains their third real point (RS ≥ 3), their fictitious
score is increased another half-point. Thus group B players can eventually attain the maximum of
number of fictitious points (FS = 2).
When a player of group C gains at least 4.5 real points (RS ≥ 4.5), their fictitious score is increased
by a half-point for the third time.
When a player achieves N/2 real points (where N is the number of rounds in the tournament), their
fictitious score is brought to 2.
Before the penultimate round, all fictitious points are cancelled and the system becomes a usual
Swiss system.
Summary table
Within each cell, the top number represents the real points and the number within brackets is the
fictitious amount added in order to achieve the Global Score (GS).
The rightmost cells of the table consider cases with more than 11 rounds (they don't include groups
A or B). Lower-case “n” in this case represents the number of rounds.
GS
0
0.5
1
1.5
Grp.A
Grp.B
Grp.C
n=9
Grp.C
n>11
0
(0)
0
(0)
0.5
(0)
0.5
(0)
0
(1)
1
(0)
1
(0)
0.5
(1)
2
2.5
3
3.5
4
4.5
5
5.5
6
6.5
7
0
(2)
1
(1)
1.5
(0.5)
1.5
(0.5)
0.5
(2)
1
(2)
1.5
(1.5)
2.5
(0.5)
2.4
(0.5)
1.5
(2)
2
(1.5)
2
(2)
2.5
(1.5)
3
(1)
3
(1)
2.5
(2)
3
(2)
3
(2)
4
(1)
4
(1)
3.5
(2)
3.5
(2)
4
(2)
4
(2)
4.5
(2)
4.5
(2)
4.5
(2)
5
(1.5)
5
(2)
5
(2)
5
(2)
5.5
(1.5)
2
(0.5)
2
(0.5)
86
3.5
(1)
3.5
(1)
4.5
(1.5)