[Cascade]

MickyB, on Jan 6 2005, 06:15 AM, said:

mikestar, on Jan 5 2005, 07:21 AM, said:

Another good question is how much lighter the games should be. Jeff Rubens in his excellent The Secrets of Winning Bridge suggests 1 point. I suspect many modern players would bid a vulnerable game at IMPS 2 points lighter than NV--in that case, perhaps the optimum is for each partner to "borrow" a point.

No way it should be 2 points lighter. Thomas Andrew's research can be read here; His double dummy analysis showed that, using the fifths count (4 - 2.8 - 1.8 - 1 - 0.4), 3NT will make >50% of the time with 24.4 points or more, and >40% of the time with 23.8 or more.

Even without this analysis it is easy to see that we are talking about a fraction of a trick which will correspond to only a fraction of a hcp.

At IMPs not vul games need about 45% and vul games need about 35% (we can do the exact math if you want).

The difference is around 10% of a trick.

With 40 hcp the each trick is worth roughly 3 hcp so the difference in our judgement needs to be about 30% of 1hcp.

One example will illustrate how fine this is:

If game needs us to get four tricks from this suit

AKQx

xxx
then

AKQ9

xxx
gives us a 47.7% chance and is enough not vulnerable

while

AKQ8

xxx
gives us a 38.6% chance and is enough vulnerable.

Basically the difference is very slight shift in attitude for both players when vulnerable.

[mikestar]

In suggesting that the modern trend might be 2 points lighter, I agree that this is actually too much. In fact I think the bast approach is something like this:

Always use the same basic numbers (points, losers Zarpoints, whatever) for invites, accepts, etc.

Now taking NV at IMPS as the norm where everthing is evaluated down the middle:

At matchpoints, be more distressed by your hand's flaws and less impressed by its good points.

Vul at IMP, be less distressed by your hand's flaws and more impressed with its good points.

Taking hand 3 as an example, I see three flaws--bad trumps, Qx, stiff A--and one good point--the excellent side suit. At matchpoinst I will invite but am worried about it and I wouldn't criticize someone who took a position and passed.

NV at Imps I invite will less worry. I would be deem pass over conservative and bidding game over agressive.

Vul at IMPs I invite with no worry at all and wouldn't criticize someone bidding game.

[Fluffy]

inquiry, on Jan 6 2005, 08:57 PM, said:

Fluffy, on Jan 5 2005, 09:15 PM, said:

I think that vulnerable game thing is overrated, in the end guessing on the right moment is what will matter the most, I mean, any judgement you can apply is gonna work better than looking at vulnerability.

Give a talk to your dad.... at imps, part of my judgement, is how close I am to game and when to push and when not too. I find it amazing you ignore condition of contest when bidding.

For being agressive when vulnerable you don't win much, in average how much, 1 IMP/hand?, 1 IMP is really a lot in average, but on certain deals you come to be agreessive only because you are vulnerable, and play ridicoulous games you could avoid if you gave a deep thought to partner's expected holdings.

[luke warm]

most of you are better with the percentages than i am... i sort of understand fluffy's view, but i don't agree with it completely... taking wayne's numbers, ie playing a vulnerable game that has a 35% chance of making, it's pretty easy even for me to see that you make 7 times out of 20... that is 500 (game bonus) x 7=3500 extra points (not counting trick value)...

i think you'd have to be off one doubled a little more than 10 of the remaining 13 times to break even (that's 200 penalty plus the lost 140 for 3M you'd have made)... that assumes you're doubled on the other 13 hands... 'course i'm not a mathmatician so i'm not sure of that... someone is tho, i'll bet

[flytoox]

I think this discussion of aggressive/solid invite/accept is not that meaningful without mentioning the hand evaluation and reevaluation. I think how to reevaluate your hand with the development of auction is more important than what discussed here. When you plan to bid a game and hope to make it, I think the vul. is not that important. It is a two side edge, if you make you win more, if you go down you lose more.

In Ben's frist example, pd's 2S didnt upgrade ur hand that much and you should invite I think(in 2/1 if u play 1M-2M as sound raise that is another story). However in Ben's fourth example, the hand becomes slammish after pd's raise.

[mikestar]

Hand 4 is slammish on playing strength but not worth a slam try becuase you need controls: you need an Ace and two Kings for the slam to be good and partner is very unlikely to have them having given only a single raise. Two Aces are possible but will leave you less than 50%.