Double Trouble as Bridge Bots Battle in Orlando by Al Levy

published in ACBL Bridge Bulletin, January 2019, PP. 24-25

The 22nd annual World Computer-Bridge Championship was held alongside the WBF’s 2018 World Championships in Orlando. The event pitted nine bots, each playing as a team of four identical bots. The first stage, a 32-board round robin, ended with the top four bots, Wbridge5 (121.49 VPs), Micro Bridge (112.93), Synrey Bridge (108.21) and Q-Plus Bridge (97.51), advancing to the 64-board KO stage. In two close semifinal matches Wbridge5 defeated Q-Plus Bridge by the margin of the carryover, 158.7 – 155 and Synrey Bridge bested Micro Bridge 87 – 78.7. The final was a rematch between last year’s finalists, with the same result, Wbridge5 defeating Synrey Bridge, 150.9 – 132.

In the close Q-Plus Bridge versus Wbridge5 semifinal, Q-Plus Bridge picked up 27 IMPs on two boards, due to revealing doubles by Wbridge5.

Hans Leber, developer of Q-Plus Bridge, reports that he, and most of the participants, concentrate on errors and fixing them, so reporting good deals requires an added look, and a find in deal 2 of the semifinal match. Looking at the N-S cards, game is excellent while 6♠ from the North side is [far] less than 50%. Q-Plus Bridge took advantage of Wbridge5’s takeout double to place cards in the bidding, and determine that slam was now a good prospect ending in a 13 IMP pickup.

Board 2
Dealer: E
Vul: N-S		 North
♠ KQ83
♥ T5
♦ AKJ63
♣ K9
West
♠ 92
♥ QJ86
♦ Q87
♣ AQJ5
 East
♠ T64
♥ 943
♦ 52
♣ T8762
South
♠ AJ72
♥ AK72
♦ T94
♣ 43
West
Wbridge5
—
Pass
Dbl
Pass
Pass
Pass		 North
Q-Plus Bridge
—
1♠
3♦
4♣¹
4NT
6♠
 East
Wbridge5
Pass
Pass
Pass
Pass
Pass
All Pass		 South
Q-Plus Bridge
1♦
2♠
3♥¹
4♥¹
5♥²
.

¹ first or second round control
² 2 of 5 key cards
opening lead ♥3, +1430
Note, even with a 4-1 trump break, the contract makes.

Q-Plus Bridge picked up 14 IMPs on board 5 of the semifinal fourth quarter, on a board also played in the finals of the three major team championships.

Board 5
Dealer: N
Vul: N-S		 North
♠ 875
♥ JT976
♦ 875
♣ J7
West
♠ 92
♥ AQ8
♦ KQT432
♣ T6
 East
♠ AJT6
♥ K5432
♦ A
♣ AQ9
South
♠ KQ32
♥ —
♦ J96
♣ K85432
West
Q-Plus Bridge
—
3♣ ¹
5♦ ²
Pass
6NT		 North
Wbridge5
Pass
Pass
Pass
Dbl
All Pass		 East
Q-Plus Bridge
1♥
4NT
6♥
Pass.
.		 South
Wbridge5
2♣
Pass
Pass
Pass
.

¹ Strong heart raise
² 1 KC
Opening lead ♠ K, +990

Wbridge5 made the fatal mistake of doubling 6♥ with two sure trump tricks, as Q-Plus Bridge, warned of the bad trump break, bid 6NT which makes on any lead as East is declarer. A safe diamond lead would be won by East, a heart to the ace reveals the 5-0 break, cashing two high diamond winners now insures 11 winners, and leading a spade endplays South for the twelfth trick. At the other table Wbridge5 was in 6♥, down two.

In the other bot semifinal match, Synrey Bridge was in 5♥ down one and Micro Bridge was in 6♥ down two. In human play the deal was played six times, twice in each of the three human-team final matches. 6♥ was the contract three times, down one or two, 4♥ was the contract twice, once down one and once making, and 5♦ was bid and made once.

Congratulations to Wbridge5 and all the bots for their dedication in advancing bridge bot play as well as offering learning and entertainment software and free online play. See http://www.computerbridge.com for all the play, the 22 year history, and information on all the entries.