Join Bridge Winners
All comments by Doug Bennion
1 2 3 4 5 6 7 8 9 ... 21 22 23 24
You are ignoring the author of this comment. Click to temporarily show the comment.
Extremely unlikely that sequence is in GIB's ‘catalogue’ of bids, so it is simming.

Simming that specific north holding against a 19-20 HCP 4-0-5-4 hand (as GIB described it), takes a loooong time (I did it), so GIB might not have ‘had time’ to analyse more than a small handful of deals.

In the few dozen deals I produced, making 5 was going to be slightly more likely than making 6. Not infrequently you were off two quick black tricks.
2 hours ago
You are ignoring the author of this comment. Click to temporarily show the comment.
How would this fly?

Pass 1 with hearts.

X is negative X of hearts.

Then transfers: 1 is 5+ spades, 1 is however you play 2, 1NT is natural because it has some situational value, 2 is diamonds … etc
22 hours ago
You are ignoring the author of this comment. Click to temporarily show the comment.
Frances: With those definitions I agree with you. When my pool of 1 overcalls is (1) 5-6 hearts and no other 5-card suits, plus (2) blacks 4-5 long — it's very close to 50/50

When my pool of 1 overcalls is (1) 5-6 clubs and no other 5-card suits, plus (2) reds 4-5 long — it's about 43/57 clubs/reds
Sept. 22
You are ignoring the author of this comment. Click to temporarily show the comment.
And when opposite the 1NT opener, responder sees 5-6 spades in his hand, overcaller will have the 5+ heart holding 89% of the time.
Sept. 21
Doug Bennion edited this comment Sept. 21
You are ignoring the author of this comment. Click to temporarily show the comment.
Here are some frequencies, I think. For the 1 case, I assumed 1 included all balanced hands (including any 5M332), or was unbalanced with other suits not longer. Tweaking that definition won't make much difference. For the 1NT case, it includes all balanced hands.

Overcaller bids 1, showing either 5-6 hearts, or 4 spades and 4 clubs.

Before he looks at his hand, responder opposite 1 can expect his RHO to have 5+ hearts 77% of the time, and 4s-4c 23%. When he looks at his hand and himself sees 5+ hearts, he can expect his RHO to have 5+ hearts 36% of the time.

Opposite 1NT by opener, 74% of the time responder's RHO will have 5+ hearts. If responder sees 5+ hearts in his own hand, RHO will have 5+ hearts 25% of the time.
Sept. 21
You are ignoring the author of this comment. Click to temporarily show the comment.
Diamonds. Play transfers there. X = diamonds. 3 = unlimited heart support, 3 just competing.
Sept. 16
You are ignoring the author of this comment. Click to temporarily show the comment.
I coded (badly) a little utility that kind of did some of the things you're trying to do. I used to include it with a software package that I used to sell. Some information here:

http://www.bridgebuff.com/matchpointoverview.html

I personally used it for a few weeks then got lazy and stopped. It was starting to produce some interesting data (maybe 250 or so deal inputs), I should have kept it up, might still.

It analyzed any aspect of your system that you chose to analyze, and ‘scored’ it relative to your matchpoint average. Say our average overall score was 58%. I might have found that our average when we opened an 11-14 1NT was 55%, when we opened 1 was 62%, when we chose not to pre-empt with a very weak hand, how we scored with RHO declarer compared to LHO declarer (compared to partner I need to sharpen my leads), how we scored when I declared compared to when partner declared etc etc.

Some have pointed out that when you measure this thing here, you must be on the lookout for that thing over there. For example. your notrump range/style and your other-suit openers, especially minors, are closely linked. I think I recall our 1NT openers were performing a little below average, but our 1M openers were awesome. That might have something to do the fact we opened 5M332 hands 1 or 1NT, so our 1M openers were ‘unbalanced’ and sharpened.

Eventually I tired of the zzzzzzzz manual input routine and gave it up.
Sept. 13
You are ignoring the author of this comment. Click to temporarily show the comment.
You are ignoring the author of this comment. Click to temporarily show the comment.
We alert the ‘strong notrump’ rebid, and also the 2M raise as approx ‘either 15-17 with 4 trumps, or unbalanced with 15+ dummy values’. And so also do all other weak notrumpers we encounter.
Sept. 12
You are ignoring the author of this comment. Click to temporarily show the comment.
We play 11-14 with transfers. More than once we've been kind of ‘gently scolded’ for not playing ‘obviously superior’ 2-way Stayman. So eventually I just had to find out how eccentric we were.

I checked the convention cards for a major international event (sorry do not recall which) for weak-notrumpers. I forget the precise totals, but expert pairs who played transfers outnumbered those who played 2-way by about 25:1 or 25:0. So eccentric we are not.
Sept. 11
You are ignoring the author of this comment. Click to temporarily show the comment.
That's a super-sweet 4333 for notrump purposes, with no weak suits, and nice spots. I have that specific holding making 3NT opposite 15-17 5(332) at 76.7%, whereas 4 makes 65.0%. Repeating for a random 4(333), 3NT makes 56.2%, a 20% drop because random isn't as sweet, and 4 at 42.7%.

A negative feature that is often (usually) overlooked for notrump evaluation is an unstopped doubleton. If I move the club Q to hearts, so the hand becomes T843 AQT8 KT9 85, that hand makes 3NT 56.0% (yes coincidentally close to random 4333), whereas 4 making shoots up to 83.4%. If instead I move the heart K to clubs, so the hand becomes T843 AT8 T9 KQ85, 3NT makes just 50.6% and 4 makes 83.3%.

4333 isn't your worst enemy, ‘xx’ is. These were all 5000 deal samples.
Sept. 10
You are ignoring the author of this comment. Click to temporarily show the comment.
Reminds me of the claim by a mathematician that there are no uninteresting numbers. Someone took him up on it with ‘well what’s so interesting about 29'? Mathematician replied with ‘easy — that’s the first uninteresting number'.
Sept. 10
You are ignoring the author of this comment. Click to temporarily show the comment.
If we played a strong notrump, we'd include 11-14 5M332 in 1, which would include all balanced hands below our 1NT range. However we happen to play a weak notrump (11-14), so we include 15-17 5M332 in 1.

You win some and lose some playing an unbalanced 1M. The major loss is sometimes by opening 1 or 1NT you miss a 5-3 M fit, even a 5-4 fit. We play a scrambly kind of Stayman which mitigates this issue (see my profile!). However it is a huge gain knowing that 1M opener always has either (1) extra M length or (2) a second ‘genuine’ 4+ suit. This knowledge permeates throughout your system. For example you can play 1NT as unconditionally forcing, with an interesting follow-up system. We play transfer opener rebids but I suspect other methods (Gazzilli?) might benefit as well without 5M332 clogging things up.

We make an exception for 18-19 5M332 hands which we open 1M.

Oh your 1 opener is always unbalanced as well, so in competition you can raise comfortably with 4-support, even 3.
Sept. 5
You are ignoring the author of this comment. Click to temporarily show the comment.
Yes 13 might be stretching it, but I get all kinds of squarish quacky 12-pointers that I don't want to force to game opposite some of our 1M openers. We never open 1M with 5332 (unless 18-19) and 1M can be frisky. 1NT is always forcing.
Sept. 4
You are ignoring the author of this comment. Click to temporarily show the comment.
The 2 rebid has a wide range. We use 2 like a 2NT rebid, only stronger. 2 might be 12-13, 2NT 10-11.
Sept. 3
You are ignoring the author of this comment. Click to temporarily show the comment.
An unstopped doubleton is a bad thing to have, but is rarely considered when evaluating a hand. This example has all suits stopped, which is good. The ‘AJ’ is a small negative, but the hand is worth an upgrade.

To illustrate my point re: the doubleton, I did three quick and dirty sims each looking at 2000 deals. The holdings are 5332 with 17 HCP, opposite balanced 8 HCP. The first 5332 has an unstopped doubleton (no better than Jx), and makes 3NT 57.1% of the time. For the second sim, the 5332 hand has all suits stopped, with Kx or Ax in the doubleton. It makes 3NT 64.5% of the time. That’s a serious difference, with the only variable being ‘xx’ vs ‘Ax’ or ‘Kx’.

For the third sim, honors were randomly scattered about. That holding made 3NT 60.0% of the time, sitting about halfway between no stopper and full stopper. Those spreads suggest the ‘average’ 17-pointer has an unstopped shorter suit approximately half the time …
Sept. 3
You are ignoring the author of this comment. Click to temporarily show the comment.
Yu: I agree that if responder doesn’t pass, that introduces much more complexity and good luck with those sims. Responder will have his own counters (especially his own ‘double’) and some of his holdings will cater better to a takeout double, others to the 1 overcall.

Re: Kit’s point. There is also an offset going the other way. Let’s say you generally prefer to double with 45xx, so that when you do overcall 1, partner won’t respond 1 with 4.

With 1 on your right, what do you do with the likes of 4-5-0-4 (1%), 4-5-1-3 (16%), even 4-5-2-2 (40%)? If you double, sometimes partner won’t have a major, and will love his diamonds, and get you into trouble. (Yes you ou could play ELC doubles there but those have issues as well.) And if you instead chose to overcall 1 with say 4-5-1-3, partner won’t show you his 4 spades and that isn’t ideal either.

Forgetting the offsets, and dealing specifically for outcomes with the 4-5-3-1 holding, I compared doubling with 1 head-to-head at both matchpoints and IMPs, for 1000 boards. They are very close. Doubling matchpoints better 19% of the time, ties 72%, and loses 10%. Doubling gains on average 0.20 IMPs per deal.

Call it a tie. I actually prefer to ‘double’ myself, because I like to use transfers starting with X in this position (1) 1 (n), so we don't have a ‘responsive/negative’ double there, so holding 4 spades we trust that with 1 partner doesn't also have 4 spades.
Aug. 30
You are ignoring the author of this comment. Click to temporarily show the comment.
Hey wait a delayed sec. Isn't that 3-5-x-x hand a red herring? This was a comparison between doubling and overcalling 1 with a 4-5-3-1 hand. Nobody doubles with 3-5-x-x, everybody overcalls, so the Moysian ‘issue’ belongs to everybody.

I'm recoding some stuff to permit a head-to-head comparison between the two ‘styles’, IMPs and matchpoints, which might prove interesting. If it seems to work OK I'll repeat for 5-4-3-1 holdings.
Aug. 29
You are ignoring the author of this comment. Click to temporarily show the comment.
As described first page, responder was limited to unexceptional hands which he would probably pass. Sure if he did find some call, it might cast a different light on which overcall was the ‘winner’, but I wasn't inclined to write a book on the subject :-)
Aug. 28
You are ignoring the author of this comment. Click to temporarily show the comment.
Marty, I didn’t calculate it, I simmed it. Opener has his 1 opener, responder his loose constraints. For the ‘universe of 1 overcalls’, overcaller has 5 hearts, with other suits shorter (I want to exclude 2-suited hands). I ask the deal-generator to deal 1000 suitable hands, and it finds 1000 of them in 3600K attempts.

The specific holding I want is overcaller with 3-5-x-x and his partner with precisely 4 spades and less than 3 hearts, and I also specify partner have a max minor suit limit of 5, so he won’t be bidding diamonds or passing the double. The generator deals 1000 suitable hands in 71500K attempts. I think you math guys call that a subset.

I’ll repeat the sim. The ‘universe’ arises 1000/3600K or 0.02777% of the time, the subset 0.0014% of the time. The subset happens for 5% of the universe (of course it is easier to simply divide 3600 by 71500). Why that isn’t the 6% I initially quoted I don’t know. I might have been dealing with heart overcalls with 5-6 hearts, might be a rounding thing, might be some small differences in constraints.

It’s possible there is something wrong with the method and if so, maybe somebody could point it out for me..
Aug. 28
1 2 3 4 5 6 7 8 9 ... 21 22 23 24
.

Bottom Home Top