Monday, March 4, 2013

Can you win this robot tournament - solutions

Last time, we looked at several problems in a 12-board robot tournament. Top was 25.

Board 1: ♠AT AK98 Q764 ♣K87. Partner invited game in hearts after his Stayman bid had been doubled by RHO. If you bid 4, you earned 16 or 23 if you found the (doubleton) trump queen (I didn't). If you passed you were below average with 5.5 or 10.5.

Running score after two: 36 (72%).

Board 3: ♠K72 KJ72 ♣AKJ64. You opened 1♣ and partner bid 1. If you were really disciplined and resisted the reverse, to rebid your nice clubs, you earned a healthy 19 (+110), assuming you didn't butcher the play. If you reversed, you received 13 for –50. If you rebid 1NT then you were getting either a top or a bottom depending on your play and the robots' defense.

Running score after six: 92.5 (61.7%).

Board 7: ♠A932 K95 AQT6 ♣KJ. You opened 1NT, partner bid 2♠ (Minor Stayman), you rebid 3 and the robot bid 3NT. If you made a move (I chose 4), you would have ended up with a 24.5 (only one other table bid the cold 6). I reasoned that the KJ were useful cards in clubs (they were) and that the robot wouldn't have bid 2♠ unless slam was reasonable.

I mentioned in the exposition of this little problem that not all humans responded 3 to the Minor Stayman bid. I can only guess that those who bid 3♣ didn't bother to read the explanation of the call. Some simply rebid 3NT, essentially denying a four-card minor. Presumably they didn't read the explanation either. I have some sympathy for these folks. The explanations are often quite inaccurate, at least as far as strength is concerned. But when they say they have a particular shape, that is usually true. [Just today, I opened 2NT, next player bid 4 and my robot doubled; the explanation was "biddable diamonds" – he had a small singleton!]

Running score after seven: 117 (67%).

Board 8:

I probably just got very lucky but I bid 4♣ (splinter) which was worth another 24.5 when 11 tricks were there for the taking. If you did anything else (or if you didn't double at your second turn) you most probably scored a 13.5.

Running score 152 (67.5%).

Board 10: ♠K982 T62 K6 ♣AQ32. East dealt and opened 1. Did you double? If you did, then you won this board in a somewhat unusual way: you wrong-sided the resulting 3NT contract by the opponents. You will have suffered a twinge of dread when it went redouble on your left, but your partner was there with his 1♠ preference bid. Most probably you would have ended up with 18.225 for down one but I got really lucky when declarer went wrong and down two for 23.45 mps.

Board 11:

As you can see, if you took the spade finesse (or you just cashed the top two spades at some point), then you made ten tricks like most other declarers for 14 mps. The danger of a diamond switch was a lot less than it might have been. Somebody managed to take 11 tricks when West got pseudo-squeezed and pitched a spade.

BTW, I always look for opportunities to sow seeds of confusion in the defenders. I therefore took the club "finesse" at trick 3 to suggest to East that his partner might have the Q.

Running score: 189.5 (69%).

Board 12: ♠J943 A76 A8 ♣AQ97. After East opened 1 in third seat, double was the call most likely to succeed. A few bid 1NT which strikes me as being absurd (15 hcp vulnerable, with only Ax in the bid suit?). Some of those got lucky making 120 or even 150 when LHO didn't lead his partner's suit. But most got their just deserts with –100, –200 or even –300.

After your double, BTW, it went 1 by partner and 2 by East. Would you have doubled again? If you did, partner would have competed to 3♣ for down one and a shade over 7 mps. If you were disciplined and passed (or even if you raised to 2), West would compete to 2♠ going down one (12.5 as in my case) or, if you were lucky, two (18.75).

Final score: 202 (67.3%), good enough for 1st place.

I hope you've enjoyed this little quiz. It isn't hard to win a robot duplicate and I don't claim that it reflects any great brilliance on the part of the player. Like any duplicate, it needs luck, some gifts and some reasonable care not to end up in unusual, no-play contracts.

What makes a robot duplicate a particularly good event to use for a bit of fun like this is that the robots are fairly predictable. If there was an alternative play/call that some other human chose, we can see what the robots' reaction(s) would likely have been if you had done the same thing.

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