[Shugart23]

This is a matchpoint question : If you know you have a 50% chance of making slam, should you bid it, knowing most of the room will stop at game and make game ?

Is your answer different in IMPS ?

Thank you

[P_Marlowe]

 Shugart23, on 2022-February-23, 12:58, said:

This is a matchpoint question : If you know you have a 50% chance of making slam, should you bid it, knowing most of the room will stop at game and make game ?

Is your answer different in IMPS ?

Thank you

Hi,

the main question is, why do you play in the room you are playing?
To train, to have fun or to win.
If you know most of the room wont even go looking for the slam, and you know,
slam is roughly 50%, stay out, if you want to want to win, ..., you are certainly
better than most in the room, and you will be able to get your scores on other boards.

With kind regards
Marlowe

[mikeh]

There are very, very few contracts where the odds are exactly 50%

AQJxxx opposite 10x requires 3-2 with the King onside: absent information from the auction, this is about 34.25%

Make it AQJxxxx opposite 10x and it still requires no 4-0 break.

Even with say AQJxxxx opposite 109x, where in the suit it is 50%, there may be a ruff in a side suit, especially but not only when one is missing an ace.

So, in the long run if one is playing the percentages, it doesn't pay to bid these 'on a finesse' slams, since they are rarely simply 'on a finesse'.

However, later in the event or in an event where one expects to have to have luck in order to do well, you may want to bid these sub-par contracts, especially if you expect more than half the field to stay out. If you go down, well you weren't expecting to win today anyway. If it works, you've picked up a chunk on your likely rivals (so long as they didn't go for the swing as well).

Echoing PMarlowe above: if you feel that your partnership is a favourite to in or be in close contention, stay out.

Of course, you'll keep track of how you are doing, and you might swing late if you feel you need a top. Personally, that's not my style. If I think I'm close enough that a top might put me over, I won't go for it. My estimates are not that precise, plus I tend to err on the side of underestimating, so I wouldn't want to snatch defeat from the jaws of victory by getting a 15% board in a 45% slam.
s

[helene_t]

If you make 12 tricks, you might get a good score even for game if many others make only 11.

If you make 11 tricks, you may get a poor score even for game if many others make 12.

So you should bid slam if you have poor declarer play and stop in game if you have better than avg declarer play.

[smerriman]

 helene_t, on 2022-February-23, 15:34, said:

If you make 11 tricks, you may get a poor score even for game if many others make 12.

So you should bid slam if you have poor declarer play

If you have poor declarer play where you're probably taking 11 tricks when 12 are available, bidding slam is probably not wise Now you're getting a 0 when at least you could have tied some of the equal other poor declarers in game.

[helene_t]

 smerriman, on 2022-February-23, 16:07, said:

If you have poor declarer play where you're probably taking 11 tricks when 12 are available, bidding slam is probably not wise

OK but I took the premise as being that 12 tricks had 50% chance, given the declarer play of the player who has to make the decision.

[Shugart23]

 helene_t, on 2022-February-23, 16:11, said:

OK but I took the premise as being that 12 tricks had 50% chance, given the declarer play of the player who has to make the decision.

yes, it's not a declarer play issue, it was as noted before: Is the king ahead of or behind my ace?

I guess I was looking at like this : suppose everybody in the room is equally good at declarer play. Then the only way to win is going to be by being better at landing in the right contract than everybody else. so, if I am able to find slams better than most in the room, should I bid it where it's on a finesse. It seems unanimous opinion is no, which I can see

[smerriman]

 Shugart23, on 2022-February-23, 16:23, said:

I guess I was looking at like this : suppose everybody in the room is equally good at declarer play. Then the only way to win is going to be by being better at landing in the right contract than everybody else. so, if I am able to find slams better than most in the room, should I bid it where it's on a finesse. It seems unanimous opinion is no, which I can see

If everyone happens to be equal at declarer play and there isn't going to be much random variation in the results - which is unlikely - then you should be bidding a slam if it makes more than 50% of the time.

The catch is as mikeh said; a finesse is not a 50% slam; there are virtually always other factors at play.

[Cyberyeti]

 Shugart23, on 2022-February-23, 16:23, said:

yes, it's not a declarer play issue, it was as noted before: Is the king ahead of or behind my ace?

I guess I was looking at like this : suppose everybody in the room is equally good at declarer play. Then the only way to win is going to be by being better at landing in the right contract than everybody else. so, if I am able to find slams better than most in the room, should I bid it where it's on a finesse. It seems unanimous opinion is no, which I can see

The answer may depend on your system, you may be playing a 14-16 no trump, and be able to determine that slam can't be worse than a finesse while the people playing 12-14 can work out it can't be better than a finesse. Now if you're playing 12-14 and you know the field plays 14-16, you can expect the field to be in it if partner has 14 and not if he doesn't, which may trigger state of the match considerations.

Also as stated most slams "on a finesse" are not really 50% as first round ruffs or extreme trump breaks make the odds slightly lower.

[AL78]

I have a loosely related question. If you are in a slam which is virtually certain to be bid by everyone else, you have a simple finesse in one side suit, and a two way finesse in another side suit, at MPs, should you do an elimination play and play A then Q in the first suit, endplaying whichever defender wins to save you a guess for the 12th trick, or should you take two finesses and go for 13 tricks, going off if both finesses fail?

Example: BridgeMaster level 3 A6.

[DavidKok]

I've never been in a slam that was virtually certain to be bid by everyone else. People are terrible at slam bidding.

[smerriman]

Virtually is the key word. All you need is a single table not in slam to make the safety play average above 50%.

That is, assuming the two finesses are 50%. In the BridgeMaster example, East started with 9 minor cards to West's 7, so after being forced to finesse West for one, you're looking for split honors, and the two-finesse route loses as often as it wins. But if the AQ were in South, the odds would favor finessing twice.

[thepossum]

In the wrong forum but here to learn. Just had an experience where a 20% minor grand got 100% against a 30% small NT slam plus one, in a small ACBL MP tourney. Admittedly GiB does not often show up in this forum

It needed a lot more than a finesse but NT did not look good. Its possible (without the knowledge of people with better skills than me) that it required a double finesse which I thought about but fortunately only went for the King, not the Jack too - but I reverted to begiiner distributions and stats on finesses

MP strategy is a very interesting ting to think about, is it not?

I forgot, it was 11th hand of 12 and things were not going brilliantly at that stage

It counted as a very happy moment .... and I am sure the rather slight psyche aspect of the bidding didn't make any difference at all

[Gilithin]

 Cyberyeti, on 2022-February-27, 02:49, said:

Also as stated most slams "on a finesse" are not really 50% as first round ruffs or extreme trump breaks make the odds slightly lower.

And on the other side of things, a better declarer might be able to organise a squeeze or endplay and therefore not need to take the finesse at all.