Follow the Action, day by day

Day 1: Saturday, August 19

After our delivery of HP8200 i7 3.4 GHz desktop computers, setting up the network connections and installing the software used to monitor play, we where ready for the robots.  With Shark Bridge having a first round bye, the others showed up ready to play.       7 entries

The schedule:
Saturday, August 19, round 1 of the seven 32-board round robin segments;
Sunday, August 20, rounds 2 & 3;
Monday, August 21, rounds 4 & 5;
Tuesday, August 22, rounds 6 & 7.  (Each round one bot gets a rest.)
Wednesday, August 23, 64-board Semifinals
Thursday, August 24, 64-board Final

Round 1:

Wbridge5 66 – 65 over Q-Plus Bridge (10.22 – 9.78 VP)
Synrey Bridge 72 – 50 over Micro Bridge (14.09 – 5.91)
Bridge Baron 70 – 56 over RoboBridge (12.78 – 7.22)

A nice defense, reported by Stephen Smith, developer of Bridge Baron.

Board 16
Dlr: W
Vul: N-S
.
.
North
♠ AJ3
♥ T52
♦ JT8762
♣ 3
West
♠ T974
♥ AK8
♦ 4
♣ KJ874
East
♠ Q852
Q976
♦ A3
♣ T95
South
♠ K6
♥ J43
♦ KQ95
♣ AQ62
West
RoboBridge
1♣
3♠
North
Bridge Baron
3
All Pass
East
RoboBridge
Dbl
.
South
Bridge Baron
Pass
.

Opening lead ♣3

The ♣3 lead was won by the ace and a club was returned.  West should play North for a singleton, but goes up with the king.  Now the contract is down but it requires careful defense.  Declarer won the diamond return, ruffed a diamond, cashed the A, K and Q, eliminating hearts, then led a trump to the ♠10.  North correctly won with the ♠A, not the ♠J, and returns the ♠J to South’s ♠K, allowing South to cash the setting club trick.  If North wins with the ♠J, a forced diamond return gives declarer a ruff and club sluff, allowing the contract to make.  Nicely done.  NS +50

Day 2: Sunday, August 20

Two rounds on the second day.  Round 2 showed a big upset, with RoboBridge winning its match against WBridge5, 67 – 59.  In other 2nd round matches, Synrey Bridge had a strong win over Q-Plus Bridge, 77 – 46, and Micro Bridge soundly defeated Shark Bridge, 107 – 23.

Round 3 brought more surprises, with RoboBridge continuing to upset, defeating Synrey Bridge 88 – 86, Bridge Baron upsetting Wbridge5, 61 – 58 and Q-Plus Bridge with a surprising big win over Shark Bridge, 87 – 44.

Synrey Bridge kept the match close against RoboBridge with a gain of 13 IMPs on a well executed elimination endplay.

Board 3
Dlr: S
Vul: E-W
.
.
North
♠ AT83
♥ K73
♦ J7
♣ A765
West
♠ 9
♥ AT2
♦ QT642
♣ K832
East
♠ KJ64
98
♦ AK985
♣ J4
South
♠ Q752
♥ QJ654
♦ 3
♣ QT9
West
Synrey Bridge
Pass
2NT
4
North
RoboBridge
1♣
3♠
Dbl
East
Synrey Bridge
1
Pass
All Pass
South
RoboBridge
Dbl
Pass
.

Opening lead ♠2

North’s ♠A won the first trick.  South’s non-heart lead gave declarer a chance.  Declarer now stripped the opponents of exit cards in preparation for an endplay.  Declarer pulled a second trump, pitched a heart on the ♠K leaving two hearts in each hand and ruffed two spades before cashing the A and leading a heart, end-playing whichever defender won the trick.  If South won the heart, declarer would get it right as North was marked with the ♣A.  At the table South won with the J and returned the ♣Q.  +710 was worth 13 Imps as Synrey Bridge was +140 in 3♠, at the other table when West, in with the A, led away from the ♣K.

After 3 rounds:
Synrey Bridge 39.02
Micro Bridge 37.86
Bridge Baron 35.43
Q-Plus Bridge 31.20
RoboBridge 29.33
Wbridge5 27.90
Shark Bridge 15.26

Day 3: Monday, August 21

The field was falling into place, with the last two round robin segments to follow the next day.  Micro Bridge took the lead after posting a 100 – 53 win against Q-Plus Bridge and an 80 – 55 win against RoboBridge.  Wbridge5 had a 4th round bye then beat Synrey Bridge 93 – 57 to come into contention, 3rd, with Synrey holding the 2nd spot defeating Bridge Baron in the 4th round 96 – 68.  In the 5th round Bridge Baron beat Shark Bridge 79 – 72, to hold on to 4th place.

After 5 rounds:
Micro Bridge 69.61
Synrey Bridge 57.98
Wbridge5 55.90
Bridge Baron 51.94
RoboBridge 51.25
Q-Plus Bridge 45.99
Shark Bridge 27.39

The 4th round found this exciting deal.

Board 9
Dlr: N
Vul: E-W
.
.
North
♠ K864
♥ Q952
♦ AT754
♣ —
West
♠ —
♥ K873
♦ K8
♣ QT97654
East
♠ T9753
J64
♦ 63
♣ 832
South
♠ AQJ2
♥ AT
♦ QJ92
♣ AKJ

In one match, Bridge Baron rested too comfortably in 3NT, making 7 on a club lead, while Synrey Bridge was in the excellent 6♠ contract by South.  In the Micro Bridge versus Q-Plus Bridge match both were in 6♠ by South.   In the other match Shark Bridge overbid to 7♠, down one on a club lead, while RoboBridge stood to gain in 6♠.

Against 6♠, the lead either beat the contract (an illogical diamond from K8), allowed the contract to make (a reasonable club from Q 7th), or gave declarer a guess (a heart lead from K873).  The auctions did little to help, with a strong opening, a Stayman inquiry, and some form of blackwood.  Do you find the heart lead?

Shark Bridge found the heart lead against RoboBridge, and with a miss-guess, the contract went down one for a wash (7♠ -1 at the other table).  In the other three 6♠ contracts, a club was led and 6♠ was made.

Day 4: Tuesday, August 22

In the 6th round RoboBridge defeated Q-Plus Bridge 82 – 76, Wbridge5 had a big win against Shark Bridge, 111 – 69, and Bridge Baron stayed in contention with a strong win against Micro Bridge, 102 – 47.  After the sixth round, barring a near blitz somewhere, the four top qualifiers (Wbridge5, Micro Bridge, Synrey Bridge and Bridge Baron) appeared to be playing for position.

A cat and mouse game between Bridge Baron and Micro Bridge ended with Bridge Baron succeeding by unblocking the KJ!

Board 20
Dlr: W
Vul: Both
.
.
North
♠ K642
♥ 86
♦ 86
♣ Q8632
West
♠ AT7
♥ 42
♦ KJ732
♣ K75
East
♠ QJ953
T9
♦ QT4
♣ JT4
South
♠ 8
♥ AKQJ753
♦ A95
♣ A9
West
Bridge Baron
1
All Pass
North
Micro Bridge
Pass
.
East
Bridge Baron
1♠
.
South
Micro Bridge
4
.

A trump lead defeats the contract, depriving declarer of a diamond ruff.  Bridge Baron led the 4, won by declarer.  After cashing a second trump, South led the ♠8, correctly won by West’s ace.  West continued with a low diamond (the jack or king is best catering to partner holding queen third, continuing with the other honor when declarer ducks), to partner’s queen, and ducked correctly by declarer.  Now East did not find the club return to take the pressure off West.  The diamond return was won by South and on the run of trumps, West avoided the endplay by discarding theKJ, allowing partner to win the eventual diamond return with the ten!  Down one.

4was the contract at the other table, as well as at three of the other four tables in the other two matches, with Q-Plus Bridge playing in 1.  In all the 4 contracts a killing trump was led.  However, except for Bridge Baron, all defenders ducked the spade lead to let declarer make the contract.

Two boards from the 6th round that were also played in the ‘human’ competition follow.  On board 2, the outcome of the aggressive 4♠ contracts depended on the opening lead.

Board 2
Dlr: E
Vul: N-S
.
.
North
♠ K6
♥ KQ
♦ 743
♣ QJ9862
West
♠ AQT432
♥ J6432
♦ K9
♣ –
East
♠ J98
87
♦ T865
♣ AK73
South
♠ 75
AT95
♦ AQJ2
♣ T54
West
Wbridge5
.
1♠
3
North
Shark Bridge
.
Pass
Pass
East
Wbridge5
Pass
2♠
4♠
South
Shark Bridge
Pass
Pass
All Pass

Opening lead ♣Q

Pitching West’s two diamonds on the two top clubs allowed 4♠ to make. At the other table, Shark Bridge rested in 3♠, +140 on a heart king lead and diamond shift.

In the Q-Plus Bridge versus RoboBridge match, Q-Plus Bridge rested in 3♠, +140 at one table and 3NT, -200 at the other table.  In the Micro Bridge versus Bridge Baron match, 4♠ was down at both tables on the heart king lead and diamond shift.

Overall the ‘human’ where more aggressive than the robots.  At only six tables out of the 66 played, a spade partial was the final contract.  While a small sample, the robots defeated 4♠ 3 out of 4 times, while in the human competition, 4♠ contracts made 24 out of 50 times.

On another board from the 6th round, 3NT was the favorite (although not best game) contract.

Board 15
Dlr: S
Vul: N-S
.
.
North
♠ KJ
♥ AQJ853
♦ T6
♣ J32
West
♠ T92
♥ T94
♦ QJ82
♣ A76
East
♠ 863
K62
♦ K975
♣ Q85
South
♠ AQ754
7
♦ A43
♣ KT94
West
RoboBridge
.
Pass
Pass
North
Q-Plus Bridge
.
2♠
4♠
East
RoboBridge
.
Pass
All Pass
South
Q-Plus Bridge
1♠
3
.

Opening lead 2

Similar N-S auctions occurred by RoboBridge, Bridge Baron and Wbridge5, all with the same lead.  Micro Bridge ws +620 in the superior 4♠ contact, and Shark Bridge was +200 making two overtricks in 3.  This deal was also played in the Bermuda Bowl, Venice Cup and d’Orsi Trophy.  As pointed out in the Daily Bulletin “This is the sort of test that the average club player will fail time after time, attacking hearts at once.  There is no way to make enough hearts without giving up a trick in the suit and then the defense will have a minimum of three diamond tricks, a heart trick and the ace of clubs.”  The correct play for nine tricks is to play diamonds to be 4-4 and a favorable lie of the clubs.   As both exists, the contract was made by Q-Plus Bridge, Bridge Baron and Wbridge5, but failed for RoboBridge after it attacked hearts first.

Interestingly, at the 22 tables in the Bermuda Bowl, 3NT was bid at 18 tables and received a diamond lead 17 times.  Two experts did go wrong.  Look up the records at the WBF website if you’re interested in who they are.  In the Venice Cup, 5 of the 19 declarers in 3NT went wrong, and in the d’Orsi Trophy 4 of the 10 declarers in 3NT went wrong.  Game contracts in hearts and spades were also popular, and made 15 of the 16 times bid in all categories.  At 2 of the 66 tables, 3 was the contact, and at one table a failed 6♠ was the result.

In the final round Wbridge5 beat Micro Bridge, 78 – 58, Synrey Bridge defeated Shark Bridge 62 – 54, and … hold the presses … Bridge Baron lost big enough against Q-Plus Bridge (93 – 47) to get knocked out of the knockout stage.  RoboBridge developer, Job Scheffers, was contacted as he left early!

The final standing:
Wbridge5 74.36
Synrey Bridge 69.65
Micro Bridge 65.87
RoboBridge 62.52
Bridge Baron 60.79
Q-Plus Bridge 59.83
Shark Bridge 26.98

The semifinals pit Wbridge5 against RoboBridge (no carryover) and Synrey Bridge (+3.78) against Micro Bridge.  The carryover only goes to a robot if, in the round robin, it both finished higher and defeated it’s opponent in their head-to-head match.  The carryover is then the lower of the VP difference in the two cases.

Day 5: Wednesday, August 23

We started the semifinal matches at 9:30 am, with the reappearance of RoboBridge.

   carryover 1-16 17-32 33-48 49-64
 Wb5  0  32  32  48  80  76  156 38 194
 Robo-Bridge  0  48  48  35  83  20  103  6  109
   carryover 1-16 17-32 33-48 49-64
Synrey Bridge 3.8 32 35.8 16 61.8 36 97.8 33 130.8
Micro Bridge  0 25 25 31 56 3 59 33 92

Day 6: Thursday, August 24

64-board Final with Wbridge5 narrowly defeating Synrey Bridge (by 1 IMP plus the carryover of 4.7)

   carryover 1-16 17-32 33-48 49-64
Wb5 4.7 29 33.7 47 80.7 30 110.7 0  110.7
Synrey Bridge  0 12 12 33 45 34 79 26  105

A good play by Synrey Bridge in the 3rd quarter almost paid off.

Board 15
Dlr: S
Vul: N-S
.
.
North
♠ J7643
♥ AJ9
♦ 87
♣ KJ5
West
♠ AQ
♥ K8653
♦ JT943
♣ 8
East
♠ KT2
QT74
♦ AQ5
♣ 632
South
♠ 985
♥ 2
♦ K62
♣ AQT974
West
Synrey Bridge
.
1
Dbl
4
North
Wbridge5
.
1♠
Pass
All Pass
East
Synrey Bridge
.
2♠.
Pass
.
South
Wbridge5
Pass
3.
3♠
.

Opening lead 8

North made the killing lead of a diamond.  Declarer now played best, losing to the K, and winning the diamond return.  Note there are no entries to East’s hand in order to cash the spade king to pitch the club loser.  Even if declarer gets the trump suit right it will be too late as North, when in with the trump ace, will return a club to partner’s ace, and a diamond return will guarantee defeat.  Synrey Bridge found the correct play, cashing the ♠A, overtaking the ♠Q with the ♠K and pitching the singleton club on the ♠10.  The “scissors coup,” cut off the defenders’ communications to get a needed trump promotion.  However, Synrey Bridge reasonable played the hearts to be 2-2 or South with the singleton jack.  Down 1 and a 2 IMP loss as the deal was passed out at the other table.

—————-
Continuing with a deal from round six, that was also played in round 1 of the championship events, the good 6 contract was not reached by any of the robots.

Board 12
Dlr: W
Vul: N-S
.
.
North
♠ 7
♥ AQJ643
♦ AJ62
♣ A7
West
♠ KT83
♥ K95
♦ 83
♣ KT82
East
♠ Q654
72
♦ 954
♣ J965
South
♠ AJ92
♥ T8
♦ KQT7
♣ Q43
West
.
Pass
Pass
All Pass
North
Wbridge5
1
3
.
East
.
Pass
Pass.
.
South
Wbridge5
1♠
4
.

6 is a difficult slam to reach, with six pairs doing so in the Bermuda Bowl, 3 in the Venice Cup and 5 in the d’Orsi Trophy.  None of the six robots that played the deal reached 6, with one reaching 6, one in 3NT, and four in 4.  This deal shows a weakness in robot slam bidding, where sophisticated bidding methods appear to be missing.  While most humans also missed the 6 slam, 14 of the 66 pairs did reach the good slam, and others made attempts at exploration.