BBO Discussion Forums: Talking Pts. XV?? - BBO Discussion Forums

Distribution point values are arbitrary, yet standardized through point count methods. One for a doubleton, two for a singleton, three for a void for short strains; one for each card over four for a long strain. During the 1970's some point count methods made the value of a void five points and a singleton three points which are in use today.

High card points, distribution points and card formation points make-up a hand's point count (Refer to Talking Pts. X????). Through the Combined Hand Equivalent Chart, combined hand points are brought together to reflect the trick level that can be reached at auction. The closer a partnership can bid the combined hand point count to it's optimum point count, the better the chance of getting a makeable contract will be.

It takes a minimum of 17 pts. with no misplays to make a one level trump bid, 20 pts. a two level, 23 pts. a three level, 26 pts. a four level, 29 pts. a five level, 32 pts. a six level, >35 pts. a seven level respectively. To verify the comparisons presented, select a completed dealt trump hand printed specimen without a bad trump split. Now, from declarer's position add-up the pre-ordained trick winners (Refer to Talking Pts. V??) held by opponents. Next, subtract the number of pre-ordained trick winners from thirteen. Now, subtract one point from the running total for each doubleton queen, singleton queen or king in the combined hands. Now, add/subtract one point respectively to/from the running total for each card formation held by the combined hands; the result being the number of natural tricks (Tricks not to be gotten by a trick taking tactics like a fineese or discard.) to be gotten.

Now, using your point count method, add-up the hcpts. in the combined hands. Next, subtract three points for each doubleton queen, singleton queen or king in the combined hands from the running total. Next, add to the running total the combined hands distribution point count and then add/subtract three points respectively for each card formation held by each hand. Now, divide the resulting point count total by three, resulting the trick count total to be gotten without a trick taking tactic (Fineese, discard, etc.).

When the trick count from the final count is greater than the trick count from declarer's count, the expectancy for making an overtrick exceeds seventy percent. When the trick count from the final point count is less than the trick count from declarer's count, either the point count method is bypassing distribution points, or card formation points are being excluded.

I find a point count method of one for a doubleton, three for a singleton, five for a void for opener and responder along with three for a card formation to be on spot.


Watch for Talking Pts.XV???

There are also the eqivalent distribution points for the Losing Trick Count: LTC: 9/6/3; MLTC: 9/4.5/1.5. One interesting exercise is to collate the Dp values for different distributions:-
----- M G ZP L MLT AZP
4333: 0 0 08 0 0.0 0.0
4432: 1 1 10 3 1.5 1.5
5332: 1 1 11 3 1.5 2.25
4441: 2 3 11 6 4.5 2.25
5422: 2 2 12 6 3.0 3.0
6332: 1 1 13 3 1.5 3.75
5431: 2 3 13 6 4.5 3.75
5440: 3 5 14 9 9.0 4.5
6421: 3 4 15 9 6.0 5.25
6430: 3 5 16 9 9.0 6.0

M is the standard 3/2/1 DP count typically added to Milton
G stands for Gorne and is the 5/3/1 count
ZP is Zar Points
L is the equivalent point count for the LTC
MLT is the equivalent point count for the MLTC
AZP is the calculation for Zar Points normalised to a king being 3 points, AZP = 3(ZP - 8)/4

One thing that should be obvious from the above table is that LTC variants overvalue distrubtion in comparison with alternative methods greatly. By contrast the 3/2/1 count undervalues distribution in comparison (not surprising perhaps as it is meant to be used without a fit). In between come the 5/3/1 count and Zar Points. One further option would be to use a flatter version of ZP that would get rid of the quarter points, namely SZP = (ZP - 8)/2. That would give:-
4333: 0
4432: 1
5332: 1.5
4441: 1.5
5422: 2
6332: 2.5
5431: 2.5
5440: 3
6421: 3.5
6430: 4

This looks like a reasonable alternative to the 3/2/1 scheme before a fit has been found, though it is precisely the simplicity of the 3/2/1 base that makes it so popular so it is not going to change any time soon. In any case, I would urge you to look at trick taking potential from hands rather than assume a 3 points per trick relationship automatically. This is precisely the same mistake that jogs consistently makes - you need to show the relationship practically before using it theoretically.

Zelandakh, on 2017-May-23, 02:52, said:

No it does not.
What you constantly overlook is something different: The objective of bidding and this should have a profound effect on hand evaluation.
From a purely constructive point of view LTC may not be the most precise method. Frankly I do not care.
In Bridge we do not bid constructively alone; we switch between modes.
Sometimes we are constructive, say when opponents keep quiet and we have strong hands.

I am not a good card holder most of the time and I suspect others have a similar problem.
Being obstructive is often best when the opponents have not yet entered the bidding.
The objective of bidding is beating absolute par most of the time and as often as not this means switching from constructive mode into obstructive mode.
The question is not, which method will let me find make-able contracts, but which methods will let me reach the correct level of a deal quickly, even if I might be an underdog making my contract.

This does not mean you should recklessly overbid, but you need to know when to stay conservative and when to be aggressive in the bidding.

Everybody understands trump fit plays a big role, but so does distribution.
The value of side suit distribution is of course more vulnerable to duplication.
Nevertheless when holding a trump fit but being balanced, it pays to be conservative, when being distributional it pays to be aggressive.
Even if you can not make your contract, chances are opponents could make something.
Experienced bidders often find out whether they bid constructively or obstructively only when dummy comes down.

To give just one example: Say partner opens 1♥

I might give a limit raise holding ♠x ♥Kxxx ♦Axxxx ♣xxx or holding ♠xx ♥Kxxx ♦AQxx ♣Qxx
When holding ♠KJx ♥Kxxx ♦QJx ♣KTx I would not use Jacoby and lock myself into hearts, but simply respond 2♣.
LTC tells me that 3NT might be more promising than 4♥ when opener is also balanced even though we have a nine or ten card fit in the major. 4♥ might simply not fetch.

This is exactly what modern LTC tells you. It applies on a trump fit and gets more aggressive the more distribution you have in addition.
I do not care whether I make my contract in the end if it still turns out to be a cheap sacrifice or beats absolute par.

This is usually true, when you bid distributional games.
You might not make it, but often you still do well. Nevertheless using LTC I am not constantly in contracts where I have to minimize my undertricks.
A sensible LTC seems to work quite nicely in practice.

If you bid games on balanced hands with a higher combined HCP and you do not make you do not do well, because opponents can rarely make anything of substance.

For slam bidding, LTC is only good for potential, but you tell partner in the bidding where you shortages are or your long side side suit is and let him evaluate accordingly.

Rainer Herrmann

rhm, on 2017-May-23, 04:01, said:

I understand that English is not your first language but I think what I wrote is incontrovertibly correct. The key phrase here is "in comparison with alternative methods". Your answer seems to address the different issue of "in comparison with optimal bidding strategy". I made no reference to that with good reason. Putting the numbers out there allows others to see them for what they are and thereby make an informed choice.

On your specific, different, point, the question to ask is how LTC/MLTC are being used. If they are being used in competitive and potentially competitive auctions then this would be a good point. The more typical limit raise auction where this comes up, on the other hand, is surely better served by a purely constructive evaluation method than one that builds in a factor to bid higher than we can make to protect against the opponents' possible contract. In reality, the competitive situations are more typically handled by use of the LoTT and its variants. Comparing LoTT, LTC and MLTC for these situations would certainly be something that could be done but it is a separate issue from the traditional application of an evaluation method, which concentrates on the constructive.

The real point that I always try to impress on people regarding the LTC/MLTC though is that, despite the marketing, this is mathematically exactly the same as a standard hcp method, just presented in a different form. I think once people look at the numbers as they really are they intuitively know that something is not right with them, and studies that have been done comparing methods back that up - both Zar Points and 5-3-1 points on a 4.5-3-1.5 base score significantly higher in terms of bidding accuracy. What I have not seen is a study comparing LoTT and MLTC (I assume even you would not suggest the basic LTC!) in terms of competitive decisions. It could be that there is a niche for the MLTC here; frankly though I am highly doubtful that a DP fix can cause HCPs to pull ahead of the LoTT for such decisions.

Zelandakh, on 2017-May-23, 02:52, said:

My reason for being partial to 3 pts. is trick point values from the six bid levels range from 2.5 to 3.0. Rather than use a decimal number to divide by when need arises, I round off to three to determine points per trick. For in the end the ultimate test is, "with no misplays does a combined hand's point count match-up to it's declarer count. For if not something is amiss with point count gathering which I address in my next posting.

bridgepali, on 2017-May-25, 14:32, said:

If 3pts is worth a trick, can you explain how a slam can sometimes be made by each side? Or, more general, 21-point games, 25-point slams, etc

Vampyr, on 2017-May-25, 18:24, said:

These type of illusions have been reported ever since Vanderbilt, his cronies and a French lass passed through the panama canal. As for making a game with 21 pts. or a small slam with 25 pts. it can't be done. Each scenario requires two more tricks at three points per trick to meet the challenge.

A source for points lies in trick taking tactics like a fineesee, discard, etc. The taking of a trick, no matter the card involved, is worth 3 pts. the average value associated with preordained aces, kings and queens. Another source can be from trick taking card formations that are not recognized to be a point source, like each uncovered trump card when combined hands have >8 in the long hand and a minimum of three cards in the short hand. Another source can be a misplay by opponents.

As for both partnerships having small slam hands, I can't offer a solution without some pondering.

In a coming posting I address as to how card formations provide points.

This post has been edited by bridgepali: 2017-July-07, 10:31