Talk:Suit combination

Suit combinations

I am not sure about showing lists of the "correct" way to play various suit combinations for three reasons:

1) There is often going to be split opinion on what is the "best" way

2) If they are calculated using freeware software then how can we be sure they are "correct"? and surely this would be original research?

3) If they are copied from publications, then what about copyright?

Abtract 19:10, 15 November 2006 (UTC)

Please have a look at the discussion on Wikipedia_talk:WikiProject_Contract_bridge. JocK 22:36, 17 November 2006 (UTC)

will do.Abtract 22:37, 17 November 2006 (UTC)

OK I have read it (again, since I had forgotten I contributed to the original debate). This only confirms my view that we are on the wrong track here. My reading of the previous debate is that these tables are coming from an editor applying a computer progam in other words original research!Abtract 22:45, 17 November 2006 (UTC)

There discussion on Wikipedia talk:WikiProject Contract bridge about the use of a well-established computerprogram to generate examples seems to have converged to the conclusion that such does not constitute a violation of the Original Research Policy. If you have a strong opposing view, it might be best to add your arguments to the discussion there. JocK 23:52, 21 April 2007 (UTC)

However the discussions converged doesn't alter the fact that using a computer (not convinced it is a "well established" program) to produce "correct" plays is original research ... how could it not be?Abtract 23:09, 22 April 2007 (UTC)

According to that rationale an example of a numerical multiplication like 1234 * 5678 = 7006652 obtained using a spreadsheet (or calculator) would be classified as 'original research'..? C'mon, anyone with a notepad and a pencil can check/derive the correct suit combinations, like anyone can check the above multiplication. It's just cumbersome, not complex. JocK 23:44, 22 April 2007 (UTC)

By the way: some time ago I checked the suitcombination examples listed in the article. All were listed in Roudinesco. However, we should still settle this discussion as the specific suitcombinations listed in the various tables referred to in this article are not all guarenteed to have been published either by Roudinesco or in 'The Encyclopedia'. JocK 23:58, 22 April 2007 (UTC)

The Bridge Players Encyclopedia

"According to The Bridge Players' Encyclopedia"... Is this an existing publication? And more importantly: why would we remove the explanation that goes with the examples now atributed to this (non-existent?) publication? IMO this last edit certainly does not improve the article. JocK 00:01, 22 April 2007 (UTC)

published by Paul Hamlyn. London, international edition edited by Ben Cohen and Rhoda Barrow ... bear in mind there were no citations in this section before my edit. Abtract 23:12, 22 April 2007 (UTC)

I see, that is the British edition of The Official Encyclopedia of Bridge. I prefer to refer to the latter (as was already done in the article) as it is much better known globally, and likely more up to date. JocK 23:49, 22 April 2007 (UTC)

I have no problems with that but there were no citations in the sections I have removed or changed ... these were clearly OR. We must be very careful not to show suggestions as though they are fact - the firsat section where I changed the examples was incorrect previously. Abtract 00:16, 23 April 2007 (UTC)

Please specify your objections against any of the examples in this discussion thread (rather than deleting 2/3 of the article without any discussion). Thanks. JocK 00:38, 23 April 2007 (UTC)

My objections are clear - this is OR. Unless citations can be given to show that these are examples and suggested lines of play from recognised published sources, then they are not allowed in Wikipedia. Examples which apparently arrive out of thin air are not good; examples arising from the application by an editor of a computer programme are not allowable; and citations from a dubious web source are just that 'dubious'. What we need in this and (other) articles are references to published sources like the "(Official) Encyclopedia of Bridge" and other writings by reputable bridge pundits.Abtract 09:22, 23 April 2007 (UTC)

I see that you have now put some citations in ... excellent. I will reconsider my objections in this light. Abtract 09:28, 23 April 2007 (UTC)

Improving

The citations help ... I have improved the 'examples' section by removing POV words. However the next section I have removed entirely for two reasons. First, it doesn't show both sides of the debate, it only shows the "correction" but not the original version; second, it simply doesn't make sense - the suggestions as to what an expert player might or might not do with Axx are garbled. Abtract 14:02, 23 April 2007 (UTC)

• the "Goal setting" section is written in a very unconvincing way and has no citations, it reads like OR ... I will remove it shortly unless it is improved. I hope someone else can see how much this article needs improvement. We must root out the POV and OR and produce good citations from reputable published sources.Abtract 16:44, 23 April 2007 (UTC)

• Sadly the "mixed strategy" section suffers in the same way. Abtract 16:46, 23 April 2007 (UTC)

POV & OR allegations

Can someone explain to me that changing:

"The correct approach is straightforward: play small towards the queen. If it loses to the king, once you have regained the lead you play towards the ten and finesse the jack. The chance you get two tricks will be close to 3/4. This is easy to see by considering the four possible ways the king and the jack can be distributed over the east-west hands. You succeed in three out of these four cases: the king and the jack in east (24% chance), the king in east (26% chance), and no honor in east (24% chance). On top of that, you also succeed in case east has singleton jack (0.5% chance). The total chance of success is therefore 74.5%."

into:

"The approach recommended by the Official Encyclopedia of Bridge is to play small towards the queen. If it loses, play towards the ten and finesse the jack. Total chance of success 74.5%.."

constitutes an improvement?

How can someone claim that in the above context "correct approach" is an POV? IMHO this gets close to a joke. If I state that "the correct answer to 5 + 7 is 12" is that a POV? Should it be replaced by: "the recommended answer to 5 + 7 is 12"? Even The Official Encyclopedia of Bridge starts the article on suit combinations with the very words "The correct treatment of particular suit combination...". JocK 17:32, 24 April 2007 (UTC)

It's very simple: we are writing an encyclopedia and our self-imposed rules are that we only use published sources and we don't use our own personal "knowledge" about what is "fact" and what isn't (this being OR). When a statement starts "the correct approach" is used it needs to be backed up by citing published sources (such as the International Encyclopedia of Bridge) ... however we must be careful because later on in the article (as was) we find that the IEOB is quoted as being "wrong" ... "aha", I hear you cry, "so we cannot quote the IEOB as a definitive source of FACT". This leads me to the (inevitable?) conclusion that we must limit ourselves to statements like "The IEOB recommends that ... ". Anything stronger than that (IMHO) is POV... Abtract 18:14, 24 April 2007 (UTC)

I think you are blinded by your fear for POV. A mathematical fact is a fact. The above citation "The correct approach .. is therefore 74.5%" contains purely mathematical facts plus references for these. And then there is this thing called progressive knowledge: the OEoB together with the later published corrections does constitute a credible source of fact. Your edits to the article (the above quotes being merely an example of these) degrade the content and IMO are approaching the border of vandalism. If the article mentions specific facts that - you feel - deserve a reference, then please place markers to make this explicit, rather than blindly delete whole sections. JocK 20:47, 24 April 2007 (UTC)

Wikipedia is not here to present "facts" as is made clear here. Cite published opinions is OK but this absolutely would not include the application, by an editor, of a computer program which may or may not produce the "best" line of play. The reason why the IEOB cannot be quoted as the "correct" line of play should be obvious from the fact that it has been "proved to be wrong" as mention in a previous version of the article. All this leads me to the wording I chose and for the removal of some sections. Please read these sections and see if they make sense to you and if you think they are justified by citation.Abtract 21:02, 24 April 2007 (UTC)

Despite my request, you again delete whole sections rather than specifying which precise "facts" you feel represent OR. I can't see this in any way as collaborating constructively. Have reverted accordingly, and made changes that - I hope - help reaching a compromise. (Can't know for sure if it will, I have to guess here as you never specified what you dislike in the section optimal versus correct play.) JocK 23:26, 24 April 2007 (UTC)

OK I am disappointed that my points above are not convincing so I will edit one line or phrase at a time giving my reason in each case ... you and others can judge as I do it. Abtract 00:05, 25 April 2007 (UTC)

I agree that we should seek a better title than "Optimal versus Correct Play". However, your change to "Effects of falsecarding" is completely wrong. I assume you are aware of the fact that all suit combination results are derived taking into account the possibility of falsecarding? (Honestly, and with all respect: If you are not, you should refrain from editing this page.) Are you aware of the fact that there is a BIG difference between a Grosvenor coup and a falsecard? The point of the section is to demonstrate the effect of sub-optimal defense. Have changed the title into "Effects of sub-optimal defense". JocK 17:29, 25 April 2007 (UTC)

In my opinion, the only thing mentioned here that might be OR is using a computer program and documenting its play; most of the problem here seems to be POV and tone, and a dispute over whether a particular source is reliable.

The phrasing "approach recommended by" is the better choice here. "Correct" should only be used if there is agreement in all scholarly sources that one line of play is the best, or if you can cite a peer-reviewed mathematical proof that the line of play produces the best results no matter what the opponent does (e.g. 74% is good, but there might exist a 76% line of play or the line of play might fail the the opponent does something unexpected).

Glancing through the recent edits, some is very good (e.g. removing the conversational tone and use of generic you) and some is not as good (e.g. prose is generally preferred to lists).

As for the reliability of the source, if there is still disagreement I suggest bringing in more sources to cite any controversial facts. Note it's not enough that the sources exist; they must be specifically referenced along with or instead of the unreliable source. Anomie 17:06, 25 April 2007 (UTC)

• Thank you for a reasoned response ... do you agree that the best way to proceed is for others to edit building on my, in part, "very good" edits? Abtract 17:55, 25 April 2007 (UTC)

No problem if you would stick to the "good" (i.e. linguistic) edits. Problem is you generate a diarhea of good linguistic edits and plainly erroneous content-related edits. It is hardly possible to seperate the two. JocK 19:36, 25 April 2007 (UTC)

I can't really say one way or the other on that, as I haven't read the entirety of either version of the article. There may be good things in JocK's edits as well, be careful to give them appropriate consideration. I suggest you continue to separate grammar edits from "content" edits as you did earlier, so discussion can center on the issues rather than being tied up with the wording. I also suggest both of you refrain from wholesale reversions. In fact, if there is a potentially contentions "content change" you should consider either asking for opinions here before making it or posting here with a detailed rationale as to why the new version is better than the old. And don't try to use anything I say as "policy", I'm just a regular editor like both of you. I'm just trying to help you work together. Anomie 19:46, 25 April 2007 (UTC)

• Thanks for responding to my request Anomie. I agree with your observation that there is no OR in this article, except that one might differ whether documenting the results of automated mathematical computations would border on OR or not. In this case there is no OR issue, as the examples chosen appear in various publications. My opponent in this debate seems to agree to this (or at least seems to change tack from objecting against potention OR to objecting against non-NPOV content). Your remark that the word "correct" should only be used "if there is agreement in all scholarly sources that one line of play is the best" is hitting the nail on its head. All sources agree that the lines of play published are optimal under the assumption of best defense of the opponents. I have no problem to change of wordings, and I would appreciate if Abtract would edit the language and grammar where suboptimal (he seems a native english speaker, I am certainly not, so linguistic edits from him will be very helpful). I hope, however, he will refrain from changing content, as he clearly has limited knowledge in the area. JocK 18:30, 25 April 2007 (UTC)

I agree, if you cite the reliable publications in which the examples appear then there is no OR. The "under the assumption of best defense of the opponents" is the part I'm not completely sure of in connection with "correct", so I'm glad you seem to be willing to give up the word "correct" in favor of "recommended by such-and-such". I don't know whether Abtract has limited knowledge or not, but even if so that is no excuse to revert without a good explanation. Definitely refrain from wholesale reversions. In fact, if there is a potentially contentions "content change" you should consider either asking for opinions here before making it or posting here with a detailed rationale as to why the new version is better than the old. Also, please review WP:CIVIL and WP:FAITH, and consider how you would react if someone replied to you the way you have replied. Remember, keep your cool and explain why instead of just saying "that's wrong". Anomie 19:46, 25 April 2007 (UTC)

Thanks again. You are right about trying to stay cool, no matter what happens. My heated reaction should be placed against the context of having to spend a lot of time restoring a well-researched article, of which 80% of the content is repeatedly deleted by a single person. If, after many requests to do so, that person finally makes an attempt to justify his behaviour, it becomes painfully apparent he has little insight into the content of the article.

Have restored the article to what it was before the major deletions occured (incorporating in fact a number of Abtract's edits), and I am confident that with your guidance (discuss significant changes here on the disscussion page before implementing) we'll manage to work together. JocK 20:21, 25 April 2007 (UTC)

What is this site that is referenced?

Does anyone know? is it a "reputable published source"?[1] Abtract 21:13, 24 April 2007 (UTC)

Warmerdam has published in the Bridge Journal IMP on the subject. I believe later editions of the OEoB have made corrections to their article 'suit combinations' based on Warmerdam's list of errors spotted. (Can't check this, as I don't have the latest edition of the OEoB). JocK 23:15, 24 April 2007 (UTC)

But the site that's quoted just seems like a personal site ... IMHO this is not a reputable published source, and its not good enough to say he has written in a mag but you cant find the reference. sorry but this citation just isnt sufficient.Abtract 00:02, 25 April 2007 (UTC)

The danger of quoting odds as being "correct"

I may be wrong here so please correct me if I am ... can we look at the numbers quoted above

• KJ with E = 24%
• no honour with E (ie both with W) 24%
• K with E 26%
• J with E 26%

I agree these are the only 4 possibilities and it adds up to 100% so it looks OK, but ...

Generalising from these numbers we get:

• two honours in one hand and none in the other = 48%
• one honour in each hand = 52%

I would argue that this cannot be correct. These are the possible distributions: 6.0 5.1 4.2 and 3.3 Two honours in one hand can arise from any of these combinations but split honours clearly cannot occur with a 6.0 distribution. Therefore split honours must be less likely than 2 and 0 ... whereas the above numbers suggest the reverse.

I know the differences are small and I am really not trying to be picky but I just want to get across the idea that saying something is "correct" in this context is dangerous and is POV. Plus it is not our job to make calculations and use unproven computer programs to suggest a "correct" line of play because this would be OR ... obviously. Our job is to refer to what published authorites recommend and, if there is disagreement, to report that. Abtract 17:25, 25 April 2007 (UTC)

Unbelieveable... this guy lacks any math skills but still feels he should interfere with an article of mathematical nature. Can someone else please react and explain the elementary errors he is making? JocK 17:39, 25 April 2007 (UTC)

interesting but not very helpful response.Abtract 17:55, 25 April 2007 (UTC)

This is so elementary: what are the chances for two honours (in this case K and J) to be distributed 1-1 or 2-0 over two hands of 13 cards each? We place the first honour in one of the hands. Which one doesn't matter. What are the chances the other honour ends up in the same hand, and what are the chances it ends up in the other hand? There are 25 slots available, 12 in the hand that received the first honour, and 13 in the other hand. Each slot has equal chance of receiving the second card. So, 12/25 = 48% chance of the honours to be split 2-0, and 13/25 = 52% chance of the honours to be split 1-1.... In Dutch we say: "schoenmaker blijf bij je leest"... Really, I advice you not to interfere with the (math based) content of the paper, it clearly is outside your area of expertice. But please feel free to edit on purely linguistic grounds, that is an area where your expertise is likely better than mine. JocK 18:55, 25 April 2007 (UTC)

Thank you for the compliment on my writing skills ... which makes it all the more surprising that you keep reverting my well thought out and well intentioned edits when Help:Reverting#Do makes it very clear that reverting is a tool to be used sparingly and mainly against vandals; now I don't think you are accusing me of being a vandal Wikipedia:Assume good faith so why do you keep reverting my edits? IMHO you should be building on my edits not reverting them - this is the way wikipedia works surely? I am on your side; I want a better wikipedia, check my edit history, I am a serious editor with a serious interest in bridge.

As to your dismissal of my "math based content" well in a way you make my point for me. My point isn't that my math is better than yours (it may well not be), it is that we should not be doing math we should be reporting what other experts have published/claimed etc. Any math of our own is original research.

I want to work with you and other editors on this, but I don't see any sign from you that you even understand what I am saying. Do you not agree that "recommended" is better than "correct" and that an editor running a computer program to produce solutions is OR? I leave you with that thought. Abtract 22:04, 25 April 2007 (UTC)

Hi guys, Looks like things are boiling over here. For the 26% /24% just think of the theory of vacant spaces - I seem to remember an article on it but I can't find it. I like to think of the 33 break or finesse example. eg AKQT opposite xxx. Playing AK (both following) then leading up to the Q from hand. Despite the Jack not coming down in 2 rounds and the 33 break initially well below 50% it is now still 'more effective' ( ;-) ) to play the Q. Simply put, RHO has 11 spaces for the J and LHO has 10. This sort of probability is confusing (see PRT and Monty hall arguments for hours of fun).

As for correct I would be cautious with that word - as is said at the start of the article there is so much that affects the odds like bidding (anyone here try to cope with a 1NT opener having a singleton?) the 'correct' line may be unique for every deal. (ok it may turn out to be the same for many similar cases but not all of them...). Perhaps you could put a definitions of 'correct' in?

Oh and neither of you are vandals. Come on! Calm down, both of you. This is how people end up getting angry and leaving which is a real shame.Cambion 13:44, 26 April 2007 (UTC)

I want to work with other editors but I do not feel the way forward is for editors to revert my work when it is done in good faith to improve the article. Policy is very clear .... rv is for vandals and is not to be used as a way of editing ... each editor should surely take the last edit at face value, consider it, revise it etc - this is the way we move forward. To revert my edits as has been done is to accuse me of vandalism. As to the specifics, I find it amazing that no-one seems able to see my main point which is that for editors to run a program to arrive at a line of play (we are not talking about a simple 123 x 456 here guys) is original research, how can it not be? Even editor calculations and statements about odds can only ever be OR/POV because it is not the place of an editor to make complex calculations, our job is to report/summarise what other experts have themselves calculated (EG Official Encyclopedia of Bridge published odds). In addition the whole tone of the article before I started was very non-encyclopedic and I have put a lot of effort into fixing this - all of which has been rv. I ask again ... take my edits at face value and where I have got it wrong or my english is not perfect, or there is a better way of saying it then edit my edits but please don't revert all my edits in one fell swoop as though I was a vandal I am not. This article does not belong to anyone Abtract 14:38, 26 April 2007 (UTC)

Goal setting

I am having difficulty believing that 2.09 tricks are better than 2.12 trick regardless of scoring method ... I also wonder what the difference is between "best" and "optimal" ... plus there are no citations in this section so I wonder if it is original research or are the citations simply missing? Abtract 22:45, 26 April 2007 (UTC)

What he is saying is that if every other person played the contract by the method that takes 2.12 tricks on average then if the same combination was played many times then by taking the 2.09 trick method you would get a higher total match point percentage. Imagine it as the 2.09 method is sometimes 2 tricks worse but and some times 1 trick worse. However, it is one trick better more times than it is 1 or 2 tricks worse Cambion 17:59, 27 April 2007 (UTC)

Thanks, I suspected it meant that but I wonder if you agree that the the explanation in the article is somewhat convoluted ... and moreover has no citations which makes it appear as OR? And I remain unhappy about best and optimal not being synonyms. Abtract 18:19, 27 April 2007 (UTC)

As improvements go ...

I just had to laugh when I saw "non-exploitive play" without definition or reference (presumably it is buried somewhere in Game theory ... all this to avoid using "recommended". I simply don't have time for this nonsense but I guaranty that when I look in again in a month or so "non-exploitive play" will be missing ... Abtract 11:11, 28 April 2007 (UTC)

Suit combination pages flash up briefly

Why do the pages like "Suit combinations - missing QJ" show up briefly, then disappear? Mark314159 (talk) 02:24, 16 February 2010 (UTC)

Those pages were unreferenced and the result of original research so they were deleted. Abtract (talk) 19:06, 16 February 2010 (UTC)

OK, but (a) Why do they flash on the screen before disappearing? and (b) Why aren't older versions available, as with other edits? Mark314159 (talk) 02:47, 17 February 2010 (UTC)

Sorry no idea. Abtract (talk) 17:05, 19 March 2010 (UTC)

delete Tables

Tables of suit combinations

The correct treatment of the various suit combinations obtained with the computer program SuitPlay is listed in separate tables. These are classified according to the honour cards (ace, king, queen, jack and ten) missing from the two hands. The tables can be reached using the links provided below.

{{Suit combinations}} That was the final prose section, preceding "See also" and other footer sections. --P64 (talk) 00:18, 19 March 2010 (UTC)

citation needed

Probably the particular suit combinations covered in the regular and "Mixed strategies" sections need specific references.

KT84:Q32 and KT87:Q32

These are so similar that any reader may suppose a clerical error by the wikipeditor --except for the mention of "small change", which is unmotivated. Why is this "small change in layout" appropriate? If the second, "Mixed strategies" example, represents a correction of some manual analysis, then it needs reference to the particular manual analysis. --P64 (talk) 00:34, 19 March 2010 (UTC)

Then change it ... your other recent edits have been good so go for it. Abtract (talk) 17:10, 19 March 2010 (UTC)

Grosvenor Gambit

The play described as a Grosvenor Gambit is not actually one. Taking the ace can hardly be described as illogical or irrational - at most it may be poor play, and there are many reasons why the defender may think it's the right thing to do. I would suggest that the entire sentence is removed. Estienne (talk) 01:33, 2 July 2010 (UTC)