IMP vs MP

[samsing]

Hi

 

Could someone explain why it is better to bid "close" games in IMP scoring than in MP scoring.

 

I know You can make a good bonus for reaching a game in IMP, and that You should bid games with a mere 40-50% chance for succes.

 

How do You calculate what the odds should be in MP scoring, for bidding game ?

 

Jorgen

[Guest Jlall]

Let's say there is a 45 % red game in MP. Lets say the entire field were to bid it. If you didn't you would get a top 55 % of the time, and a bottom 45 % of the time, for an EV of 55 % on the board. Let's say everyone bid it, and so did you. You would always get 50 % on the board. Let's say no one bid it, but you did. You would average 45 % on the board.

 

Another consideration, let's say game is tough to make and the field will only make 9 tricks in hearts because they didnt find your quadruple squeeze. In this case you will get 100 % on the board no matter what, but you take an unnecessary risk if you bid it (in case the quadruple squeeze doesn't work). Playing it well will almost always gain you matchpoints.

 

Now, let's say you're playing a team game. If you bid a 45 % vul game that your counterparts will not bid and make you will win 10 imps. If you go down, you will lose 6 imps. This means you gain 1.2 imps on average. If you don't bid it and they do, you will lose 1.2 imps on average. Clearly it's better to bid this.

 

Also, unlike MP if you make a great play to make 4 but you're only in 3, the gain is 1 imp instead of 10.

[joker_gib]

quadruple squeeze

Can you explain pls Justin !!??? ROFLLLLL

 

 

Alain

[helene_t]

The short answer is that at matchpoints, you should bid game when the prospects are above 50%.

 

The logic goes like this: Each of your competitors at the other tables either do or do not bid game, and make either enough tricks for game or one less. Suppose all declarers make the same number of tricks.

 

If the prospects of making game is, say, 51%, bidding game will, on average, earn you 0.51 MP against those who do not bid game and cost you 0.49 against the same competitors. A gain in the long run. By the same token, a prospect of less than 50% will cost you in the long run.

 

Whether all declarers actually make the same number of tricks doesn't matter, as long as the expected number of tricks made are the same at each table.

 

However, if you have particular expectations regarding your table vs the field, matters may be more complicated.

 

For example, if you are playing against the weakest pair in the tournament, you should not bid accordingly more aggresively: If you make 1NT+2 while all competitors make either 1NT+1 or 3NT-1, you already have a full top. So there is no point in bidding 3NT even if it has slightly more than 50% chance thanks to the weak opposition.

 

Also, if partner bids 5♣ and you consider raising to 6, it may be a good idea to do so at matchpoints even if the prospects are slim, on the basis of the idea that the field will be in 3NT+1 so 5♣= is as bad as 6♣-1. (But of course, partner is not stupid, he also knows it is matchpoints, and he must have good reasons to bidding 5♣ anyway).

 

Playing in a weak or very diverse field, the difference between MPs and IMPs is smaller: the difference between 1NT+1 and 1NT+2 is likely to be neglible because all kind of crazy things will happen in the field, so most competitors are either below 120 or above 150. So "matchpoint strategy" is mainly something that applies to strong, homogenous fields.

 

At Total Points, bidding a 50% nonvulnerable game can earn you 250 and cost you 190, so the difference is small and even smaller at IMPs. Vulnerable, the figures are 450 vs 240. So the rule that you should bid more stretchy games at IMPs applies almost only when vulnerable.

[inquiry]

quadruple squeeze

Can you explain pls Justin !!??? ROFLLLLL

 

 

Alain

I guess a quadruple squeeze is two double squeeze played on two different hands.

 

Squeeze jargan can get complicated, but I guess I would consider "quadruple squeeze" as what is called a hexagonal squeeze. A hexagonal squeeze is one in which you both opponents have to guard against threats in three suits. See... http://www.bridgeguys.com/Squeeze/HexagonSqueeze.html

 

Then there is a family of hedgehog squeezes that have similar properties to that of the hexagonal squeezes.

[joker_gib]

Never heard of this hexagonal squeeze, tx Ben ! :P

[Echognome]

I was wondering if the hexagonal squeeze was related to George Coffin. I recognised the name from the "Great 88" 5-card endings.

 

http://www.rpbridge.net/9p01.htm

 

Some of the other great names are:

 

Undercut

Squeeze Scoop Finesse

Split Squeeze

Contra Squeeze

[Guest Jlall]

Quadruple squeeze was just a joke lol.

[mila85]

I think that 50% game should not be played at MP. Mainly when the field is weak and strange things can happen.

 

Imagine there is 4♥ contract depending only on finesse.

Weak players can play 2♥= or 5♥-1. 3♥+1 will defeat these players.

[zasanya]

The thing to remember at mps is that your ops are not your ops!Your ops are all those other pairs sitting your way.So spare a thought to what the other pairs sitting your way would do on this hand and do something better than that ! :(

[pclayton]

4 suit squeezes have been recently discovered. Seems like its basically a non-simultaneous simple squeeze against both opponents. There's your quadruble squeeze LOL.

[samsing]

Thanks for the responses.

 

But this raises a new question. How do You calculate the % chance for making game ?

 

I suppose if I have 18 p and partner raises my major opening to the 3-level (10-12 points in my system) the chance should be well above 50% but what if I hold lets say 14 p, and my partner shows the same support. What are we talking here 40-50% ?

 

Jorgen

[pigpenz]

Quadruple squeeze was just a joke lol.

Justin was just hoping that the girl in his picture there would run a simple squeeze on him ;)

[barmar]

Thanks for the responses.

 

But this raises a new question. How do You calculate the % chance for making game ?

There's no simple answer to this, it mostly comes from experience.

 

In most cases, I think players don't actually try to compute percentages, they just think in terms of categories like: excellent game prospects (26+ combined HCP + a good fit in the trump suit); close games (24-25 HCP, or a Moysian fit, or likely wasted values somewhere); stretching for game (22-23 HCP); etc

 

At MP scoring you generally only bid close games or better. But the IMP scoring table makes it OK to stretch for games when vulnerable.

 

The converse of this is that at MP it's often more worthwhile to sacrifice.