The American Contract Bridge League’s 8th
annual World Computer-Bridge Championship was held in
History
At the suggestion of New York Times bridge editor Alan Truscott, I petitioned the ACBL
in 1996 to hold a computer-bridge event…and thus was born the World
Computer-Bridge Championship.
The ACBL inaugurated this annual
computer-bridge championship in 1997 as a way of encouraging computer-bridge
software developers to accelerate their robots’ development to expert
class. Since then progress has
accelerated and the top robots have advanced significantly, but not yet to the
ranks of expert. The top robots often
exhibit expert play but not consistently enough to be considered expert.
This championship has been held
every year at an important human international bridge event, with me as the
organizer. The preceding seven
championships were held three times at ACBL NABCs, three times at World Bridge
Federation (WBF) World Championships and last year at the European Bridge
League’s (EBL) first European Open Championship. When hosting this championship, the ACBL, WBF and EBL have given
both financial and organizational support.
For a complete history and details of previous championships go to
ny-bridge.com/allevy/computerbridge.
Technical remarks
A bridge “table” consists of a central server, or Table Manager
(TM), and four connecting computers, which “seat” the robots. The TM distributes the four hands of each
board to the robots. Play proceeds
automatically with the TM receiving and passing information to the robots and
recording the play. This year P4 2.4 GHz/512
MB PCs were used, running under Windows XP.
The speed of play was set at 2 minutes per pair per deal, approximately
half that of human play.
Without getting into the
details, most of the robots are programmed with a combination of
knowledge-based AI, or sets of rules, and search-based AI, or simulations.
Preparation
This is very much a group effort between the organizer, the
computer-bridge software developers and the ACBL. An administrative committee sets the Conditions of Contest with
input from the software developers and bridge experts.
It is important that the software developers understand their opponent
robots’ methods in advance of the competition so that they can prepare
defenses. In human play, advance notice
is not necessary when unusual systems are not allowed, as is the case in this
competition. However, in
computer-bridge play the robot developers need time to program defenses and store information about the opponent robots’
methods. Contestants are required to
submit a Convention Card (CC) one month before the competition. This is in the form of a spreadsheet, with
over 100 questions. Once the CCs are
published contestants ask each other (through email) even more detailed
questions about their methods and conventions.
Since this information is stored in the robots’ memories before the
competition begins, few alerts are
necessary during play. In the few
instances where alerts are required the pertinent information is input into
memory and play continues.
Play format
The competition is in the form of team matches, with a team’s
robots seated N-S at one table and E-W at the other table. The boards in a match, or part of a match
such as a 16-board set, are played sequentially, first at one table (closed
room) and then at the other table.
The five-day event starts with a
24-board round-robin with the top four robots advancing to a 64-board knockout
(KO) semifinal with carryover. The
round-robin is scored on an international 30-VP scale, where the winning team
receives a maximum of 25 VPs for a 52 or more IMP victory. To earn a carryover in a semifinal or final
KO match, a team must both win its head-to-head round-robin match against its
KO opponent and finish higher in the overall round-robin standing. The carryover is the lesser of these two VP
differences
The Bridge World
Editorial on the use of a qualifying round-robin preliminary to a knockout
phase
In the August 2004 issue of the Bridge World,
Jeff Rubens comments that while a round-robin preliminary segment may provide a
substantial amount of guaranteed play for entrants who may have endured
considerable expense to play, there are so many flaws that its use may
sacrifice tournament quality.
Some of the flaws mentioned for human-play are:
the scoring system, where the closer it is to win-loss, the greater the danger
that small differences will have enormous consequences, and the closer it is to
total score, the greater the danger that winning margins of strong teams
against weak teams will be relevant; sportsmanlike dumping is a theoretical
threat in late matches that will determine who are matched in KO round, or who
qualifies for the KO round; and preparation against many different systems is
required which severely increases the preparation needed.
In computer-play some of these flaws do not
exist and others are minimized. The robots
aren’t allowed to dump and their brains can be checked if there is an
accusation. The robots aren’t
influenced by the state of affairs so the timing of the matches is irrelevant,
except for the suspense of the spectators.
[In fact, this was the case this
year. Viewing Table 2 we see that the
stronger robots played each other in early matches therefore greatly reducing
spectator suspense at the end. In the
future the highest ranked robots will be matched near the end of the
round-robin rather than near the beginning.] In our competition the preparation needed to study and defend
against all the opponents is limited.
This is due, in part, to only allowing systems and conventions that are
common international methods so that the software developers can concentrate on
improving their robots’ bridge skills and spend less time on understanding and
defending against complicated methods.
In our competition Convention Cards are due one month before the
competition. While the list of
allowable conventions is large (standard methods vary around the world) the
robots’ photographic memories easily digest the methods of their
opponents. For certain classified
uncommon treatments the robots explain the meaning to the opponent robots
through electronic or manuals means. We
use a 25-VP scale. It is not close to
win-loss and the winning margin against weak teams is softened as the VP award
is topped at 25, not 30. As can be seen
in this year’s competition, beating-up on the weaker teams did not affect the
round-robin standing. With one
exception, the top five round-robin finishers scored 25 VPs against the weakest
three teams. The one exception was
The
competition
The round-robin ended with Bridge Baron topping
all competitors with 147 VPs. Closely
behind were Wbridge5, with 145 VPs, Jack, with 138 VPs and
The
robots, their developers and the final round-robin standing are shown in Table
1. Table 2 shows the IMP/VP results of
each round-robin match and the round that each match was played.
Table 1: Entries along with the 24-board round-robin final standing.
|
Robot |
Developers |
Country |
VPs |
|
Bridge Baron |
Stephen Smith, George Yanakiev, Jason Rosenfeld and
Tom Throop |
|
147 |
|
Wbridge5 |
Yves Costel |
|
145 |
|
Jack |
Hans Kuijf, Wim Heemskerk and Martin Pattenier |
The |
138 |
|
|
Tomio and Yumiko
Uchida |
|
131 |
|
Q-Plus Bridge |
Hans Leber |
|
108 |
|
|
Ian Trackman and
Mike Whittaker |
|
63 |
|
|
Rodney Ludwig |
|
37 |
|
Sabrina |
Pierre Cormault and Gérard Joyez |
|
3 |
Table
2. Round-robin match results
|
|
Jack |
Bridge
Baron |
Wbridge5 |
|
Q-Plus Bridge |
|
|
Sabrina |
Position VPs |
|
Jack IMPs Round VPs |
|
72-15 1 25-5 |
47-53 2 14-16 |
27-58 3 9-21 |
44-45 4 15-15 |
74-6 5 25-3 |
152-1 6 25-0 |
124-8 7 25-0 |
3 138 |
|
Bridge
Baron |
15-72 1 5-25 |
|
62-36 3 20-10 |
56-21 4 22-8 |
81-19 5 25-4 |
95-35 6 25-4 |
114-33 7 25-1 |
121-12 2 25-0 |
1 147 |
|
Wbridge5 |
53-47 2 16-14 |
36-62 3 10-20 |
|
60-31 5 20-10 |
80-30 6 24-6 |
94-6 7 25-0 |
102-10 1 25-0 |
151-5 4 25-0 |
2 145 |
|
|
58-27 3 21-9 |
21-56 4 8-22 |
31-60 5 10-20 |
|
77-40 7 22-8 |
70-44 1 20-10 |
136-2 2 25-0 |
141-1 6 25-0 |
4 131 |
|
Q-Plus
Bridge |
45-44 4 15-15 |
19-81 5 4-25 |
30-80 6 6-24 |
40-77 7 8-22 |
|
101-22 2 25-2 |
152-18 3 25-0 |
184-4 1 25-0 |
5 108 |
|
|
6-74 5 3-25 |
35-95 6 4-25 |
6-94 7 0-25 |
44-70 1 10-20 |
22-101 2 2-25 |
|
55-31 4 19-11 |
97-32 3 25-3 |
6 63 |
|
|
1-152 6 0-25 |
33-114 7 1-25 |
10-102 1 0-25 |
2-136 2 0-25 |
18-152 3 0-25 |
31-55 4 11-19 |
|
112-19 5 25-0 |
7 37 |
|
Sabrina |
8-124 7 0-25 |
12-121 2 0-25 |
5-151 4 0-25 |
1-141 6 0-25 |
4-184 1 0-25 |
32-92 3 3-25 |
19-112 5 0-25 |
|
8 3 |
Q-Plus Bridge did not make the semifinals but
it did win the round-robin “best-played hand” award for its play on this deal
which occurred in the forth round against Jack. 26 IMPs were at stake. 13
IMPs to Q-Plus Bridge if it makes 6© and 13 IMPs to Jack if it fails.
|
||||||||||||||||||||
|
West |
North |
East |
South |
|
Q-Plus |
Jack |
Q-Plus |
Jack |
|
1§ |
Pass |
1© |
1ª |
|
2ª |
Pass |
4ª |
Pass |
|
5§ |
Pass |
6© |
All Pass |
With the 1ª bid by South,
West’s hand became bigger, and the Q-Plus Bridge robots bid to an overly
aggressive heart slam. South led a low
spade, and declarer finessed, drew trumps, eliminated diamonds and spades,
cashed the §A and followed with a low club. The defense was helpless and Q-Plus Bridge
scored +1430.
Semifinal
In the semifinals, round-robin
first place finisher, Bridge Baron, had a 14 IMP carryover against fourth place
finisher,
The last time Jack played Wbridge5 in a
championship KO stage was the 2002 finals.
That final was the closest KO final in computer-bridge history with Jack
winning by 1 IMP. This year Jack
continued its winning ways, this time defeating Wbridge5 more comfortably,
157-118. In the other semifinal match
Bridge Baron defeated Micro Bridge 166-126.
Board 64 of the semifinals earned Jack 17 of its 39 IMP
margin of victory.
Board 64 North
Dlr: West ª 6 5 3
Vul: E-W © Q 10 4
¨ 10 8 7 2
§ 10 8 5
West East
ª 8 ª A K Q 4 2
© 8 2 © K 9 3
¨ A K Q J ¨ 6 5
§ K Q J 7 6 3 § A 4 2
South
ª J 10 9 7
© A J 7 6 5
¨ 9 4 3
§ 9
West |
North |
East |
South |
|
Jack |
Wbridge5 |
Jack |
Wbridge5 |
|
1§ |
Pass |
1ª |
Pass |
|
2¨ |
Pass |
2© |
Pass |
|
3§ |
Pass |
4NT |
Pass |
|
5ª1 |
Pass |
5NT |
Pass |
|
6¨2 |
Pass |
6NT |
All Pass |
1 two key
cards and the §Q
2 one king
|
West |
North |
East |
South |
|
Wbridge5 |
Jack |
Wbridge5 |
Jack |
|
1§ |
Pass |
2ª |
Pass |
|
3¨ |
Pass |
3ª |
Pass |
|
3NT |
All Pass |
|
|
Jack found the perfect contract, 6NT by East. Jack took thirteen tricks after the lead of
the ªJ, +1470. 5NT asked for kings. East was
planning to bid 6§ if West didn't have the ¨K. Indeed, if West has ª8 ©Q2 ¨AQJ7 §KQJ763, for example, 6§ is the superior contract.
At the other table, Wbridge5 did not reach
slam. The strong 2ª bid crowded the auction and Wbridge5 stopped in
3NT, played from the wrong side. Jack
found the deadly lead of the ©10. Now the defenders took the first five tricks
for down one. Jack normally leads low from honor-third. However, after simulating possible layouts, Jack saw the danger
of blocking the suit and therefore chose the ©10 lead instead of the ©4. The unexpected extra bonus was the ©10 lead won the first
trick and hearts could be continued through the king.
In the other semifinal semifinal match, both teams
arrived at 6§ and could have
been beaten on a heart lead.
|
West |
North |
East |
South |
|
Bridge
Baron |
|
Bridge
Baron |
|
|
1§ |
Pass |
1ª |
Pass |
|
3§ |
Pass |
4NT |
Pass |
|
5ª |
Pass |
6§ |
All Pass |
|
West |
North |
East |
South |
|
|
Bridge Baron |
|
Bridge
Baron |
|
1§ |
Pass |
2ª |
Pass |
|
3¨ |
Pass |
3NT |
Pass |
|
4§ |
Pass |
4ª |
Pass |
|
4NT |
Pass |
5© |
Pass |
|
6§ |
All Pass |
|
|
At
one table
Semifinals
|
Carryover
|
1-16 |
17-32 |
33-48 |
49-64 |
Total |
|
Bridge |
14 |
48 |
38 |
43 |
23 |
166 |
|
|
0 |
49 |
33 |
19 |
25 |
126 |
|
|
|
|
|
|
|
|
|
Wbridge5, France |
2 |
19 |
42 |
20 |
35 |
118 |
|
Jack, The |
0 |
58 |
21 |
26 |
52 |
157 |
For the
second year in a row Jack and Bridge Baron were playing for the
championship. There was no carryover as
Jack defeated Bridge Baron in their head-to-head round-robin match and Bridge
Baron finished higher in the round-robin standing.
Jack
defeated Bridge Baron, 157-97, to claim the championship for the fourth year in
a row.
Final
|
Carryover |
1-16 |
17-32 |
33-48 |
49-64 |
Total
|
|
Bridge |
0 |
16 |
39 |
13 |
29 |
97 |
|
Jack, The |
0 |
40 |
22 |
40 |
55 |
157 |
To show the level of
play of these two robots, the second quarter of the finals is presented. This 16-board set was the only set that
Bridge Baron bested Jack.
Board
1 North
Dlr:
North ª 5 4 2
Vul:
None © 10
4
¨ 10
7 3
§ A K 7 6 4
West East
ª K J 6 ª A Q 8 3
© A K Q 9 7 © 5
2
¨ J 5 2 ¨ A
Q 9 8 6
§ Q 9 § J 5
South
ª 10 9 7
© J
8 6 3
¨ K
4
§ 10 8 3 2
West North East South
BB Jack BB Jack
Pass 1¨ Pass
1© Pass 1ª Pass
3NT
West North East South
Jack BB Jack BB
Pass 1¨ Pass
1© Pass 1ª Pass
2§1 Pass 2¨2 Pass
4ª
1 asking
2 No club stopper and
less than 3 hearts; does not promise 5 diamonds
Jack
reached the best contract, 4ª on a 4-3 fit, and made six when Bridge Baron led a heart and didn’t
return a club after winning the ¨K. Jack reasonably placed the final contracted at 4ª. Bridge Baron lucked out when the opening leader made the normal
low club lead from AKxxx. 2 IMPs to
Jack.
Board
2 North
Dlr:
East ª Q J 10 8 3
Vul:
N-S © 8
7
¨ Q
9 2
§ K J 10
West East
ª A 9 2 ª K 2
© A Q 6 5 3 © 10
4 2
¨ 8 5 ¨ A
K 6 3
§ 5 4 3 § A 9 8 7
South
ª 7 5 4
© K
J 9
¨ J
10 7 4
§ Q 6 2
West North East South
BB Jack BB Jack
1¨ Pass
1© 1ª Dbl1 2ª
4©
West North East South
Jack BB Jack BB
1§ Pass
1© 1ª Dbl1 2ª
4©
1 support double
The
ªQ was
led at both tables. Jack cashed the ©A
before ruffing a spade and led a heart toward the ©K. Bridge Baron took the heart finesse. +420 at both tables.
Board
3 North
Dlr:
South ª A 8 7 5 4 3 2
Vul:
E-W © A
Q 10 7
¨ J
7
§ -
West East
ª J 9 ª Q 6
© 5 4 3 © K
9 6 2
¨ K 10 5 ¨ A
Q 6
§ K J 10 9 7 § A Q 6 3
South
ª K 10
© J
8
¨ 9
8 4 3 2
§ 8 5 4 2
West North East South
BB Jack BB Jack
Pass
Pass 1ª Dbl Pass
2§ 2ª 4§ Pass
4NT Pass 5ª Pass
6§ Dbl
West North East South
Jack BB Jack BB
Pass
Pass 1ª Dbl Pass
3§ 4ª
At
one table Bridge Baron had an accident.
It appeared that robots don’t always play as if they are clones of each
other. 4§ should suggest a stronger
hand and West took his partner to have a stronger hand and reached 6§x, -800. At the other table Bridge Baron took a
reasonable shot at 4ª, +420 and 9 IMPs to Jack.
Boar
4 North
Dlr:
West ª A 7 6 5 2
Vul:
All © 5
4
¨ A
J 7 3
§ A J
West East
ª Q 10 8 4 ª K 9
© Q 8 © A
J 10 9 3 2
¨ 9 6 ¨ 10
8
§ K Q 9 5 3 § 10 8 2
South
ª J 3
© K
7 6
¨ K
Q 5 4 2
§ 7 6 4
West North East South
BB Jack BB Jack
Jack BB Jack BB
Pass 1ª 3©
Both
Easts viewed a 3© preempt as best. Humans would
not have the stomach to bid 3© with this vulnerability. With five losers -100 was the result at both tables.
Board
5 North
Dlr:
North ª 9 2
Vul:
N-S © A
J 10 9 6
¨ K
6
§ J 9 8 3
West East
ª K J 3 ª Q 6
© K Q 7 4 © 8
5 3
¨ A J 10 5 ¨ Q
7 4 2
§ 7 5 § A K 10 4
South
ª A 10 8 7 5 4
© 2
¨ 9
8 3
§ Q 6 2
At
both tables South opened 2ª and after three passes the West led the ©K. Declarer won the ©A, ruffed a heart and led a diamond to the ¨K
and returned a diamond. +110 at both
tables.
Board
6 North
Dlr:
East ª 6 2
Vul:
E-W © K
J 10 9 7 6
¨ Q
9 8
§ 10 4
West East
ª K J 5 ª A 10 4
© - © A
Q 8 5 2
¨ A K J 10 2 ¨ 4
3
§ K Q 9 6 3 § A 7 5
South
ª Q 9 8 7 3
© 4
3
¨ 7
6 5
§ J 8 2
West North East South
BB Jack BB Jack
Jack BB Jack BB
1© Pass
2¨ Pass 2NT Pass
3§ Pass 3NT
Both
sides missed the good 6§ contract when both Wests took a conservative view and passed 3NT. If East held ªAQx ©KQJxx
¨xx §xxx, then 4NT over 4§ would still have been safe.
Board
7 North
Dlr:
South ª 10 8 5 4
Vul:
All © 2
¨ 10
9 8 3
§ Q 9 4 2
West East
ª 6 2 ª A K J 9 3
© Q 9 7 © J
8 6 4
¨ K Q J 7 ¨ 4
2
§ 10 7 5 3 § K 8
South
ª Q 7
© A
K 10 7 5
¨ A
6 5
§ A J 6
West North East South
BB Jack BB Jack
1©
Pass Pass 1ª 2©
All
Pass
West North East South
Jack BB Jack BB
1©
Pass Pass 1ª
At
one table Jack made a bad 2© bid. After ªA, ªK, ªJ ruffed and overruffed,
West returned the ¨K. Declarer won the ace and
played ©A and ©K pitching a diamond. After §A, §J East won the §K and returned a
diamond. West’s fourth diamond forced
declarer to ruff and South was end played at trick 12, -300. Declarer could have saved one trick by
either ducking the first diamond or not pitching a diamond on the second
heart. At the other table Bridge Baron
should Dbl over 1ª and reach 2§ or push N-S higher. Defending 1ª, Bridge Baron took seven tricks with two hearts, two heart ruffs, two
clubs and one diamond, +100. 9 IMPs to
Bridge Baron.
Board
8 North
Dlr:
West ª A 10 8 7 5 3
Vul:
None © -
¨ K
10 7
§ 8 7 3 2
West East
ª K J 2 ª Q 6
© K J 8 4 © A
10 6 3
¨ Q J 3 ¨ A
9 8 5 4 2
§ K J 6 § Q
South
ª 9 4
© Q
9 7 5 2
¨ 6
§ A 10 9 5 4
West North East South
BB Jack BB Jack
Jack BB Jack BB
1NT Pass 2§ Pass
2© 2ª 4©
Both
declarers guessed to play the ©A first but still had to lose one trick in each suit
for down one. It is too difficult to
reach the best contract, 3NT.
Board
9 North
Dlr:
North ª A Q 10 7
Vul:
E-W © 9
3
¨ Q
8
§ J 5 4 3 2
West East
ª 8 5 ª 9 6 4 3
© J10 8 6 2 © 7
5 4
¨ J 10 9 ¨ 7
6 3
§ A Q 9 § 10 7 6
South
ª K J 2
© A
K Q
¨ A
K 5 4 2
§ K 8
West North East South
BB Jack BB Jack
Pass Pass 2§
Pass 2¨ Pass 2NT
Pass 3§ Pass 3NT
Pass 4§! Pass 4©!
Pass 4NT Pass 5©
Pass 5ª Pass 5NT
Pass 6NT
West North East South
Jack BB Jack BB
Pass Pass 2§
Pass 2NT Pass 3NT
All
Pass
Jack
could not avoid 6NT with South promising 23-24 hcps and North holding 9 hcps
plus a five-card suit. 4§ was forward going with at
least five clubs and 4© showed less than 3 clubs (4¨
would show 3+ clubs). While 6NT turns
out to be a 32% slam it was a good bet before the actual hands were
revealed. Bridge Baron stopping
conservatively at 3NT. 11 “slightly
lucky” IMPs to Jack, but it would have been 11 “slightly lucky” IMPs to Bridge
Baron if diamonds weren’t 3-3.
Board
10 North
Dlr:
East ª 10 9 6 2
Vul:
All © 4
2
¨ A
Q 6 5 4
§ J 3
West East
ª K Q ª A J 8 7 4
© K Q 8 7 6 © 10
9 5 3
¨ J 10 8 ¨ 3
§ A 10 4 § K 9 7
South
ª 5 3
© A
J
¨ K
9 7 2
§ Q 8 6 5 2
West North East South
BB Jack BB Jack
Pass Pass
1NT Pass 2§ Pass
2© Pass 4©
West North East South
Jack BB Jack BB
Pass Pass
1NT Pass 2§ Pass
3§1 Pass 3¨2 Pass
3© Pass 4©
1 a
minimum with at least 5 hearts
2 transfer forcing a 3©
bid
At
one table Bridge Baron made 12 tricks for +680 on the §J lead and a club return
after South won the ©A. At the
other table Jack led a spade and South returned a diamond after winning the ©A,
+650. 1 IMP to Bridge Baron.
Board 11 North
Dlr:
South ª Q 10 7 6
Vul:
None © K
4
¨ J
6
§ K 8 4 3
West East
ª J 8 2 ª A 4 3
© Q 8 6 © A
J 10 9 7 3 2
¨ 10 3 ¨ K
9
§ A Q 10 9 2 § J
South
ª K 9 5
© 5
¨ A
Q 8 7 5 4 2
§ 7 5
West North East South
BB Jack BB Jack
Jack BB Jack BB
3¨
Pass Pass 4©
At both tables the bidding and play were
identical. The opening ª5
lead went to the ª10 and ªA. Both declarers led a club to
the §A and passed the ©6. Next the §Q was led and both Norths defended best by not covering. Declarers discarded a spade and continued
with the §10 covered and ruffed; cashed the ©A; crossed to the ©Q and cashed the §9;
making 11 tricks (seven hearts, three clubs and a spade) at both tables for
+450 and a wash.
Board
12 North
Dlr:
West ª A J 9 7 2
Vul:
N-S © K
10 7 2
¨ 9
§ 8 6 4
West East
ª 8 ª K Q 6
© A Q 5 4 3 © J
9 8
¨ A K Q 10 6 ¨ 7
4 3
§ 3 2 § A K 10 7
South
ª 10 5 4 3
© 6
¨ J
8 5 2
§ Q J 9 5
West North East South
BB Jack BB Jack
1© 1ª 2ª 3ª
4©
West North East South
Jack BB Jack BB
1© Pass 2§ Pass
3¨ Pass 3© Pass
4©
Both
declarers made 10 tricks, losing a spade and two hearts. At one table Jack led a diamond. Bridge Baron took the heart finesse and then
a heart to the Jack, losing two hearts and a spade. At the other table Bridge Baron led the ªA. Jack played the ©A and a heart to the Jack, losing two hearts and a
spade.
Board
13 North
Dlr:
North ª A J 4 3
Vul:
All © A
J 4
¨ 6
4
§ K J 9 8
West East
ª Q 9 8 7 ª K 10 2
© 10 7 2 © K
9 8
¨ Q 3 2 ¨ K
10 8 7
§ A 7 2 § Q 5 3
South
ª 6 5
© Q
6 5 3
¨ A
J 9 5
§ 10 6 4
West North East South
BB Jack BB Jack
Jack BB Jack BB
1§ Pass 1©
Pass 1ª Pass 1NT
Pass 2©
Both
declarers went down two tricks, -200.
When Jack declared 2© Bridge Baron led the fourth best spade and declarer
played the ªJ? to East’s ªK. After a spade return to
North’s ªA, a low diamond went to South’s ¨9! and West’s ¨Q. Now the defense did well by returning a
trump and a trump continuation when East won the ©K. Declarer won in dummy and led a diamond ¨A?
and ruffed a diamond, ruffed a spade, played the last trump and then
miss-guessed clubs and took no more tricks.
At the other table Jack led a diamond to the ¨K
and ¨A and declarer erred by playing trumps. East won the ©K and returned a trump. Now declarer played a
diamond to the ¨J? and ¨Q. A spade went to dummies ªJ and East’s ªK. East led a trump won by the ©Q. When declarer miss-guessed clubs East returned a spade removing
one of North’s entries to the long club and West did well to duck a club, thus
removing the second entry to the long club.
Declarer eventually lost two more diamonds.
Board
14 North
Dlr:
East ª A Q
Vul:
None © K
Q
¨ K
Q 5 3
§ Q J 5 3
West East
ª J 8 7 6 3 ª K 9 2
© 10 9 8 6 5 © A
J 4 2
¨ 8 ¨ A
9 7 2
§ 9 3 § 4 2
South
ª 10 5 4
© 7
3
¨ J
10 6 4
§ A K 10 5
West North East South
BB Jack BB Jack
1¨ Pass
Pass Dbl Pass 1NT
Pass 3NT
Opening
lead: ª6
West North East South
Jack BB Jack BB
1¨ Pass
Pass 2§ Pass Pass
Dbl! 2NT Pass 3§
Pass 3NT
Opening
lead: ©4
At
one table Bridge Baron (West) led a spade and declarer had no chance. The defense took four spades and two aces,
-100.
At
the other table the auction was strange indeed. Bridge Baron miss-described its hand when it bid 2§ rather than Dbl in the
balancing seat. Jack (East) led a low
heart and West played the ©5 and declarer won the ©Q. East captured declarer lead of the ¨Q
with the ¨A and led back a spade, +460.
Based on the play at trick one East knew West held © 10
9 8 6 5 but rather than settle for down one East returned a spade knowing from the bidding that North could
not have nine tricks...not a good idea.
Computers act differently than humans.
Humans would have cashed the four heart tricks first and then attacked
spades. 11 IMPs to Bridge Baron.
Board
15 North
Dlr:
South ª A 3
Vul:
N-S © 7
5
¨ A
K J 10 7 5 4
§ 6 2
West East
ª J 9 4 ª Q 10 8 6 5
© Q J 10 © K
8 4 2
¨ 6 2 ¨ Q
9 8
§ A K 9 8 4 § 3
South
ª K 7 2
© A
9 6 3
¨ 3
§ Q J 10 7 5
West North East South
BB Jack BB Jack
Pass
Pass 1¨ Pass 1©
Pass 3¨ Pass 3NT
All
Pass
Opening
lead: §A
West North East South
Jack BB Jack BB
Pass
1§ 1¨ 1ª 1NT
Dbl1 2¨ 2ª Pass
Pass 3NT Dbl
1 support double
Opening
lead: ª9
At
one table Bridge Baron made a good decision to lead the §K. With a low club lead declarer has an easy 10 tricks. West continued with the §A? and then led the ©Q. Cashing the §A was a mistake but Bridge
Baron recover nicely. Declarer ducked
the ©Q and won the ©J return, then cashed the club winners squeezing
East. East discarded four spades. Declarer cashed the ªA and ªK. If East discards a low heart it will be endplayed, but East found
the ©K discard and declarer had to go down one, -100.
At
the other table Bridge Baron’s bidding appears adventurous, but a simulation
after the 2ª bid produced a greatly different result then the simulation before the
2ª
bid. However, for a more cooperative
auction, 3¨ at North’s second turn was best.
2¨ followed by 3NT eliminated South from the auction. If 3NT was right Bridge Baron could have
ended in 2¨, and if 3¨ was right Bridge Baron could not get there. After the spade opening lead declarer took nine tricks, +750 and
13 IMPs to Bridge Baron.
Board
16 North
Dlr:
West ª Q 9 8 7 5 3
Vul:
E-W © J
4
¨ Q
5
§ 6 3 2
West East
ª 10 ª A J 6 4
© K 9 © Q
8 7 5 2
¨ 10 9 8 4 2 ¨ J
§ A 10 8 7 4 § Q 9 5
South
ª K 2
© A
10 6 3
¨ A
K 7 6 3
§ K J
West North East South
BB Jack BB Jack
Pass Pass 1© Dbl
Pass 1ª Pass 2¨
Pass 2ª Pass 2NT
Dbl
Opening
lead: ©K
West North East South
Jack BB Jack BB
Pass Pass Pass 1¨
Pass 2ª
Opening
lead: §5
Even
after the ©K lead, declarer only had 7 tricks, -100. In 2ª declarer won the second club and tried to discard a heart on the third
diamond. The defense ended with two
diamond ruffs, the ªA, §A and one heart, +110 and 5 IMPs to Bridge Baron.
Skill and Luck
This
set of sixteen boards shows that many IMPs can be gained on both skill and
luck. The luck includes inferior but
lucky contacts, bad bids that work out well and good bids that work out poorly,
vulnerability, and timing of scores. Of
course the luck balances out in a long match.
While 16 boards are not enough to rule out luck playing a significant
role, 64 boards greatly reduce the luck factor.
Board
1 saw Jack bid well to avoid 3NT.
However, luck was with Bridge Baron.
Bridge Baron reached the bad 3NT contract and made when the opening
leader made the normal forth best lead from AKxxx. Jack did well to reach the excellent 4ª contract and was unlucky
not to have gained 9 more IMPs.
On
Board 3 Bridge Baron had an accident at one table and made a good decision at
the other table. The accident cost 9
IMPs, while the good decision, to bid game, came at an unlucky time. It reduced the total score from 630 (if BB
played in 3ª) to 380, and gaining only 3 IMPs.
[As can be seen from this board
and boards 14 and 15, Bridge Baron often takes unilateral shots at game with
great success.]
Board
7 saw Jack pay for a bad bid and Bridge Baron get away with a “less bad”
bid. The vulnerability made a difference
also. Had both sides been
non-vulnerable, the margin would have been only 5 IMPs rather then 9 IMPs.
Board
9 saw Jack gain 11 IMPs when diamonds divided 3-3 (31.75%). If not
Board
14 saw Jack give away 11 IMPs on defense.
This was caused, in part, by Jack’s interpretation of Bridge Baron’s
hand based on the bidding and, in part, by the way computers play, namely, if
there are two ways to get to the same ending it doesn’t matter which way you
take.
Board
15 saw Bridge Baron defend 3NT well enough to gain 13 IMPs.
Board
16 saw Bridge Baron make a good decision to gain 5 IMPs.
In
this set of boards, both sides were rewarded for good play with the “lucky”
IMPs gains and lost by both sides.
General remarks
After 296 boards Jack demonstrated the most consistent good play
and the title of computer-bridge world champion is well deserved. Bridge Baron, Wbridge5, Micro Bridge and
Q-Plus Bridge also demonstrated fine play.
The level
of play of the top robots has greatly improved over the past seven years, with
the top programs such as Jack, Bridge Baron, Wbridge5, Micro Bridge, Q-Plus
Bridge and GIB (not entered in this championship for the past two years) making
great progress. Before this
championship began in 1997 the best robots were barely approaching Intermediate
play. Now the best robots would be hard
to beat in club play and a pair of Jack-Jack robots would be stars. This has been demonstrated recently in
matches pitting expert human players against a team of Jack robots (Australian
Bridge, Vol. 34, No. 5, October 2003, p.4 and International
Computer Games Association Journal, Vol. 27, No 1, March 2004, p. 52).
For more information on the World Computer-Bridge
Championship, including its history, past championship results, articles and
photos, go to computerbridge.com or ny-bridge.com/allevy/computerbridge