Talk:Hand evaluation

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I am aware that there are some articles covering parts (Point count and High-card point) of this article but I believe there is a need for a single article covering this subject in total. I hope others watching bridge articles will agree but if you don't please let me know ... I am new at this but very keen - be gentle!Abtract 22:05, 8 May 2006 (UTC)

I'm grinnin' its a pretty good presentation. Terryeo 08:01, 20 May 2006 (UTC)

[edit] HCP - one fifths

This is growing into a nice overview article. What do you folks think: should we add hand evaluation rules (alternative to HCP) derived from double dummy analysis on large sets of hands? Or is this too theoretical? (I'm thinking about Thomas Andrews' work.) JocK 12 June 2006.

To be honest, I don't know anything about it, so I'd be interested. However, if the section becom too long, you could just give an overview here and link to a new article. Duja 06:51, 13 June 2006 (UTC)

I have never heard of it so it may well be a useful addition (for me anyway!) but if it is as theoretical as you suggest, then I agree that a separate article linked here might be best - like Zar Points.Abtract 08:37, 13 June 2006 (UTC). I just found this http://bridge.thomasoandrews.com/ which may be useful - no time to read it yet.Abtract. I see this is a private site so I think we ought to know JocK if you are Thomas Andrews or closely associated with him? Abtract 09:04, 13 June 2006 (UTC).

Me, Thomas Andrew? That would be sneaky! :) No, I don't know the guy. From a theoretical point of view on hand-evaluation, his research seems very useful though. For instance, it leads to hard data on what is the best point evaluator for no-trump contracts (http://bridge.thomasoandrews.com/valuations/cardvaluesfor3nt.html). The optimal high-card point evaluation rule appears to be: A = 4.0, K = 2.8, Q = 1.8, J = 1.0, T = 0.4. (Quite close to standard HCP!) Obviously, the result has limited practical significance as with 40 points per board you can not bid your hand accurately within 0.2 point. JocK 13 June 2006.

OK as you will see I have added his site in as further reading. If you want to do more go ahead but bear in mind it is hardly mainstream. Abtract 18:08, 13 June 2006 (UTC).

thomaso I am Thomas Andrews, and a quick note. The 4.0/2.8/1.8/1.0/0.4 evaluator is optimized for 3NT contracts, not notrump contracts in general.

The problems with fractional valuations is that, while they can be 'optimized' we still have to base bidding on a 'yes/no' response. For example, after a 1NT opening, when do you leap to game? There's no realistic way to always bid game if you have 24.2 or more points, combined, and not bid game with fewer combined, because you really have three paths: Pass, Invite, Jump. If the 1NT opening is 14.6-17.4, then you obviously want to jump to game with 9.6 points. You want to pass with 6.8 points. But do you really want to invite with 7 points? With 9.4 points? No. So you are going to miss some hands where you and partner have at least 24.2 points, and bid some games where you and partner have less than 24.2.

So, while this evaluator is interesting, I'd hesitate to ascribe any practical value to it.

Well you heard it here on this page first - maybe I was a little quick in adding it to further reading, but honesty surely deserves its own reward?Abtract 20:12, 13 June 2006 (UTC).

Hi Thomas, nice to meet you. You are too modest: if your 'fifths evaluator' is optimised for the decision whether or not to bid 3NT, it *is* optimised for notrump contracts in general (i.e. for deciding whether to stay in partscore or head for game). If you mean to say that an avaluator optimised for the decision 'game-or-not' is not necesarily suited for the decision 'slam-or-not', you are obviously right. But then: which evaluator is?

Clearly, no-one is proposing to use such non-integer evaluators in practice. The practical value of having obtained such an optimal 'vector-evaluator' lays in the fact that it shows the Work-count to be close to the optimal evaluator for deciding whether to or not to stay in part-score on notrump hands.

As an aside: ever contemplated evaluating the newer methods described here? (Zar, NLTC, ...) JocK 13 June 2006.

[edit] LTC - one thirds

Here's a simple modification that should make the LTC somewhat more accurate.

After the initial calculation, subtract one "tick" for each A, add one "tick" for each Q and add 2 ticks for each J. Three ticks = one LTC. Then AKx, AKx, AKx, AKxx = 4 LTC- 4 ticks = 3 LTC - 1 tick But KQx, KQx, KQx, KQxx = 4 LTC + 4 ticks = 5 LTC + 1 tick And KQx, KQx, KQx, KJxx = 4 LTC + 5 ticks = 5 LTC + 2 ticks

Another suggestion is to round up with 2 surplus ticks and round down with one.

NOTE: In the revised version, Jacks are counted in the initial calculation.

Jillbones 02:17, 16 November 2006 (UTC)

I expect you looked at 5.3 and 5.4 in the article where you will have seen very similar improvements to the LTC method and citations as to the source. If you know publications that show this 'one third point' improvement, then you should include it in the article at the appropriate place. If, on the other hand, this improvement is your own idea or that of a friend then this would count as original research and be against policy so shouldn't be included.Abtract 10:15, 16 November 2006 (UTC)

[edit] Law of Total Tricks

I'd like to direct your attention to the article on DONT, which references the Law of Total Tricks. Clicking on that link brings the page here, which is both unsatisfying and misleading. First of all, the Law of Total Tricks is not a hand evaluation method - simply counting the combined trumps cannot tell you if you are likely to make 3 tricks or 13. Secondly, at the very least, clicking on the link should put you at the Law of Total Tricks section of the article. If anyone could help resolve this issue, I should greatly appreciate it.Eljamin 18:05, 20 November 2006 (UTC)

Excellent idea I have improved the link as you suggested.Abtract 23:13, 20 November 2006 (UTC)

I've split the article from this one and I'll fix the link in DONT; with due respect, I think that Abtract was a bit overzealous in merging the topics into this article; by itself, the LoTT is a tactics rather than a method of hand evaluation: it doesn't say how worth is your hand but which tactics to employ in competitive auction. Plus, it's now long enough that it definitely deserves a separate page. Duja► 12:49, 21 November 2006 (UTC)

Perhaps you might like to discuss the merits of splitting it off before you do so and refain from discussing how over zealous I may or may not have been. Abtract 13:03, 21 November 2006 (UTC)

OK, here I am. Actually, I only recently noticed myself (before Eljamin's suggestion) that LoTT was merged here (and I don't recall you "discussed the merits of merging before doing so", as the LoTT article had a pre-history before it ended up here, but let's leave that behind us). But I can't find a good reason why it should remain merged, as LoTT has well-defined scope outside of mere hand evaluation, as I said above. Actually, the contexts of wikilinking ("mine" was from Balancing (bridge), Eljamin's from DONT) had nothing to do with hand evaluation. Yet the reader ends up here. Besides, I expanded the LoTT article (and it has potential for further expansion), so that its backmerge here would really result in a huge article. In addition, LoTT section was in the middle of this article, right between LTC and playing tricks, which are, I think you agree, on a fairly similar line of reasoning while LoTT appear to came straight from Mars in the context. I don't mind a brief coverage about LoTT here, but not more than a sentence or two. We also have Zar Points in a separate article. (which, I still maintain, are more related with the subject of Hand evalauation than LoTT) Duja► 11:48, 22 November 2006 (UTC)

As I said I am not against a separate article ... leave the old stuff here and I will cut it down and refer to the main article.Abtract 13:17, 22 November 2006 (UTC)

OK I have made it just a brief summary and linked to the main article.Abtract 13:36, 22 November 2006 (UTC)