Humans versus Jack (3)

Computer Bridge 3; World Champion Jack in Action

To gauge the playing strength of Jack, we matched him against seven strong Dutch pairs. This instalment covers matches 4-6.

Last time I reported Jack's good started against three pairs of Dutch experts. Frankly, we were quite relieved. We knew that Jack could do some very good things, but he always seemed to have lapses. In retrospect, Jack's lapses are almost always explainable, but that doesn't ease our disappointment.

Jack's opponents were strong and very experienced. However, though they had played a lot of bridge, they had almost no experience playing against a computer. Unused to the situation, former Dutch champion Paul Felten made a mistake he would never make against fellow human beings.

From the match against Eric van Valen and Paul Felten:

West deals N/S vul 9 5 4 3 10 5 3 K Q 10 3 A 2 K 8 7 K 4 J 4 J 10 8 6 4 3 N W E S Q J 10 9 8 7 9 8 6 2 K 9 7   A 6 2 A Q J 6 2 A 7 5 Q 5

West JackW North EvV East JackE South PF pass pass pass 1 pass 2 pass 4 pass pass pass

West led the J and Paul, still trying to light his cigar, called for dummy's 2. Only then did he ask to know how Jack led from KJ10. Too late! East won the K and switched to a spade. As West had the K, the defenders took four tricks to beat the contract before Paul could discard a loser on dummy's diamonds, as he could if he had called for dummy's A at Trick 1 and started trumps at Trick 2.

This play is all the more obvious if you know that Jack plays 'Jack Denies' opening leads, marking East with the K. Technically, the deal is not interesting at all. Any other time and against any other opponent Paul would never have made a mistake like this. But playing against a computer is apparently not the same. Underestimation of the opponents? Lack of concentration? Who knows? However, at this time 'the human factor' is still an important variable. By the way, after this board Paul was wide awake and Felten - van Valen won deservedly with 60 -43.

On the board just mentioned we won 9 IMPs (NS average +320), but it gave us little satisfaction. This partscore deal (directions rotated for convenience) pleased us, however:

South deals Both vul 10 7 2 Q J 7 6 4 2 K 9 6 5 Q J 8 5 3 4 3 K 8 5 3 J 2 N W E S A 6 10 5 A J A Q 10 8 7 4 3   K 9 4 A K 9 8 7 6 2 Q 10 9 -

West EvV North JackN East PF South JackS - - - 1 pass 1NT 2 3 pass pass pass

Van Valen led the J, and after that 3 was unbeatable. The contract did require some technique, however, as there appear to be too many losers in spades and diamonds. Drawing only one round of trumps fails, as East can get a diamond ruff. Jack ruffed the J, drew trumps with dummy's Q and J and led a spade. East ducked and the K won. Then Jack played two more trumps to reach this ending:

South deals Both vul 10 7 - 7 6 K 9 6 Q J 5 - K 8 5 J N W E S A - A J A Q 10 8   9 4 A K Q 10 9 -

In his samples, Jack had a clear view of the lay-out. He played the 9 (a spade works as well) and East won the J. After taking the A and the A, East played the A. If declarer ruffs he loses two more tricks and goes down one. But of course Jack didn't ruff. Instead he discarded his last spade, and East had give dummy the fulfilling trick with the K. These things are really 'a piece of cake' for our champ! It doesn't help East to win the first spade (or discard the A later). East will always be thrown in and forced to give dummy a trick with the K. The NS average was +50, so 3 just making won 3 IMPs.

After this defeat we felt a little more anxious. The next two pairs were Bakkeren-Bertens and Ramondt-Westra. You can hardly find stronger pairs in the Netherlands. But Bakkeren-Bertens (who shortly after this match won the European open teams!) had an off-day. Some misunderstandings cost them dearly and Jack gave nothing back.

This deal shows some accurate bidding by Jack to recover from a start with which many would not agree (they would open 1 instead of 1NT).

From the match against Ton Bakkeren and Huub Bertens.

South deals N/S vul Q 7 6 K Q 9 6 2 7 2 A 7 3 J 10 5 A 8 4 3 K 5 4 9 8 6 N W E S 9 3 10 7 J 10 9 8 6 3 10 5 2   A K 8 4 2 J 5 A Q K Q J 4

West HB North JackN East TB South JackS - - - 2NT pass 3 pass 3NT1 pass 42 pass 4 pass 4NT pass 5 pass 6 pass pass pass

¹ 5+2
² transfer

In Jack's system, opening 2NT with a 5-4-2-2 pattern is permissible unless the long suits are both majors. South's 3NT rejection of North's 3 transfer bid was a special conventional bid that showed five spades and only two hearts. Then came a key bid, North's 4---in Jack's system a second transfer ... to spades, making South the spade declarer and protecting South's diamonds against the opening lead. North asked for keys and bid the right-sided spade slam after receiving a '1430' 5 reply showing 0 or 3. 6 by North would be doomed after a diamond lead by east. South made an easy twelve tricks and won 6 IMPs (NS average +1190).

The match against Vincent Ramondt and Berry Westra was much tougher. Neither side gave the other much opportunity to score. Somewhere along the way Westra had to make the right decision in 6. The right choice would win 12 IMPs. At such moments, I found it very difficult to remain a calm and objective kibitzer. Luckily for Jack (or should I say 'us'?), Westra chose wrongly and Jack won 10 IMPs. The next board earned only about 1 IMP, but a double squeeze against the crème de la crème of Dutch bridge is always nice.

From the match against Vincent Ramondt and Berry Westra:

South deals N/S vul 8 5 4 2 A Q 6 J 10 9 3 2 J 9 6 3 K 10 7 7 4 K 10 6 4 2 N W E S Q J 10 J 9 5 2 K Q 5 9 8 3   A K 7 8 4 3 A 8 6 A Q 7 5

West VR North JackN East BW South JackS - - - 1NT pass 2 pass 2NT pass 3NT pass pass pass

West led a club and the J won. The J won the second trick and declarer followed with the A and another diamond. Westra played back a club and declarer ducked, reaching:

South deals N/S vul 8 5 4 A Q 6 10 9 - 9 6 K 10 7 - K 10 6 N W E S Q J 10 J 9 5 2 - 9   A K 7 8 4 3 - A Q

Double-dummy, East must shift to hearts, but understandably he continued clubs. Jack took his ace, cashed the A and led a heart towards the Q. On the 10 East could afford to throw a heart but on the next diamond he was squeezed in the majors. He let go a heart and declarer threw the 7. Next came a spade to the K. This squeezed West, who had to discard from a remaining K10 and K. After 28 boards Jack had lost by 8 IMPs, a very good result in view of the calibre of the opposition.

After six matches the scoreboard looked like this:

Jack	-	Hanneke Kreijns & Just vd Kam		74 - 53
Jack	-	Erik Janssen & Jeroen Top		43 - 51
Jack	-	Jan van Cleeff & Vincent Kroes		61 - 46
Jack	-	Paul Felten & Eric van Valen		43 - 60
Jack	-	Ton Bakkeren & Huub Bertens		67 - 32
Jack	-	Vincent Ramondt & Berry Westra		45 - 53

The seventh and last match would be against internationals Gert-Jan Paulissen and Bart Nab. Could anything still go wrong? Because of another appointment I could not attend the match, but I had a lot of faith in Jack. This began to melt a little when Hans Kuijf phoned me about an hour before his departure. His laptop collapsed and he had to copy some CD's from another computer. A bad omen? At two o'clock at night I came home and the first thing I did was read my email. What had happened?

To be continued...

Wim Heemskerk