comparing systems

[rbforster]

Let's say you hold Qx JTx AQx AK98x and all vul someone opens a strong club on your right. You're playing Mathe. Do you pass or bid 2C?

Good hands should pass, especially ones with lots of defense like this. they are going to have a worse than field part score auction unless you bail them out. Pass and lead a club against 1N.

[Mbodell]

Any interest in this?

 

I'm just catching up on the forums after christmas/new years, but I'm interested in this. One thing I'd caution is how you pick hands. I'd deal them randomly selecting all hands that have a strong club for opener and then allow the rest of the hands to fall as they may (including negative responses and opponents interference). Otherwise you get false relations like my system handles the goulash and freaks but falls apart on part scores and interference but the former are "more interesting" so it scores better than it should on this sort of research project.

[straube]

I'm just catching up on the forums after christmas/new years, but I'm interested in this. One thing I'd caution is how you pick hands. I'd deal them randomly selecting all hands that have a strong club for opener and then allow the rest of the hands to fall as they may (including negative responses and opponents interference). Otherwise you get false relations like my system handles the goulash and freaks but falls apart on part scores and interference but the former are "more interesting" so it scores better than it should on this sort of research project.

 

I look at deals always starting with the North hand. If it has a one club opener, then I pick it. If it opens something else I toss the hand. If it passes, I look at the East hand and also toss the deal if it does something other than pass or 1C. Etc. That's how I'm getting 1C for various seats. I also toss the deal if after opening 1C the next hand does something other than pass. I think there are chances for deal selection bias here but that they're pretty small because I'm really not looking at how the auction might proceed until I've decided whether the deal is suitable or not.

 

Personally what I'm most interested in which initial responses to a strong club prepare the partnership best for a future contested or uncontested auction. Obviously some systems have more gadgetry than others and I'm also interested in this, but (for example) knowing whether 1D should be 0-7 or 2-way (good or bad hand) or GF any or GF some etc is my primary interest.

[mycroft]

I would pass the interference hand; but if I were AKT98x I'd probably overcall. Yes, letting them have a bad auction is good, but making 2♣ is also good. AK98x is just an invitation to get doubled and go -200 into a partscore.

[awm]

I'd pass the given hand, although my rule regarding such things is not "strong hands pass" as rbforster suggests, but rather "balanced hands pass." There's no point in making a risky two-level club bid on a flat hand with this much defense. I might double 1♣ if that showed clubs (but it doesn't for me).

[awm]

Something seems a bit odd about the deals so far. Correct me if I'm wrong but it seems like twelve deals in:

 

(1) There have been no double negative responses, even though sims indicate they are about 20% of responder hands.

(2) While there were a few occasions where not everyone reached game, there have been no hands where (some) game wasn't good.

 

Am I wrong about these? They seem to suggest some skew, although perhaps it's something about the model for opener's LHO interfering?

[straube]

Something seems a bit odd about the deals so far. Correct me if I'm wrong but it seems like twelve deals in:

 

(1) There have been no double negative responses, even though sims indicate they are about 20% of responder hands.

(2) While there were a few occasions where not everyone reached game, there have been no hands where (some) game wasn't good.

 

Am I wrong about these? They seem to suggest some skew, although perhaps it's something about the model for opener's LHO interfering?

 

I chalk it up to a small sample size. I've noticed game/slam on every hand but I'm using the methodology I described and looking at BBO random deals.

[akhare]

I chalk it up to a small sample size. I've noticed game/slam on every hand but I'm using the methodology I described and looking at BBO random deals.

 

I would recommend using a Dealer script for the hand generation and posting it to make everyone agrees that it's representative. It may make sense to build in some bias into the script (like eliminating balanced 16-18 opposite balanced GF).

 

If you aren't comfortable with the syntax, many of us can help...

[straube]

Just a reminder to everyone. We've had some folks join us recently in this endeavor and they (and all of us) need to explain their auction...each bid unless patently obvious. Also it would help greatly if the entire auction is submitted including cue bids etc. Please also check back on your post and try to answer questions that others may have...and resubmit an auction if you think it needs to be changed. In a sense we're bidding each system together. My personal goal is to determine which initial responses to 1C work best. I've already not been able to post an outcome or two because there was no final auction agreement and I don't think I should interpret what the final result might be. Thanks everyone for participating.

[Mbodell]

Just a reminder to everyone. We've had some folks join us recently in this endeavor and they (and all of us) need to explain their auction...each bid unless patently obvious. Also it would help greatly if the entire auction is submitted including cue bids etc. Please also check back on your post and try to answer questions that others may have...and resubmit an auction if you think it needs to be changed. In a sense we're bidding each system together. My personal goal is to determine which initial responses to 1C work best. I've already not been able to post an outcome or two because there was no final auction agreement and I don't think I should interpret what the final result might be. Thanks everyone for participating.

 

See my post in one of the threads where I always will do this, although often by editing the auction within 5-30 minutes of posting it.

[nige1]

Thank you Straube.

I hope to use your deals to practice and refine Jasmine ♣, outlined here

 

IMO, after posting an auction, contributors should take the time to rate possible final contracts at the form of scoring that Straube specifies. I don't think that double-dummy analysis, using the actual East-West hands is important. Much more interesting would be the results of computer-simulation using random defending hands by those with access to appropriate software.

 

I will edit my posts to give marks out of 10 (a subjective estimate).

 

But it would be great if somebody could compute, for each contract reached,

• At pairs, the likely percentage score
• At teams, your expectation in imps.

[relknes]

Just a thought, but it might be fun to look at 3rd and 4th seat 1♣ structures seprately from 1st or 2nd seat 1♣ structures. I would not be at all surprised if one set of responses worked well for 1st and 2nd, while a different set worked well for 3rd and 4th.

[straube]

Just a thought, but it might be fun to look at 3rd and 4th seat 1♣ structures seprately from 1st or 2nd seat 1♣ structures. I would not be at all surprised if one set of responses worked well for 1st and 2nd, while a different set worked well for 3rd and 4th.

 

I think you're right. At this point I'm just mixing 3rd/4th deals in as they occur, but we are using an entirely different 3/4 structure and I think Justin is as well. If you use a different 3/4 structure, just identify it as such and when I post outcomes you can cross compare them with others.

[Mbodell]

I think you're right. At this point I'm just mixing 3rd/4th deals in as they occur, but we are using an entirely different 3/4 structure and I think Justin is as well. If you use a different 3/4 structure, just identify it as such and when I post outcomes you can cross compare them with others.

 

Our system varies, but only slightly, by seat and vulnerability (which is why I explain 1♣ differently on some hands), but the continuations over 1♣ are basically the same (some point ranges shifted slightly). Basically when 1st and 2nd red, and 4th always, 1nt is 12-14 and 15-17 balanced goes in 1♦, when 1st and 2nd white, and 3rd always, 1nt is 10-12 (10-~13 in 3rd), and 13-15 balanced goes in 1♦. The non-1♣ auctions changes more for us between 1/2 seat and 3/4 seat, but these shouldn't really come up in this series.

[antonylee]

IMO, after posting an auction, contributors should take the time to rate possible final contracts at the form of scoring that Straube specifies. I don't think that double-dummy analysis, using the actual East-West hands is important. Much more interesting would be the results of computer-simulation using random defending hands by those with access to appropriate software.

 

I can do the simulations (DD with random E/W hands) but I think this would miss an important point, which is information leaked in the auction. What would be more convincing would be DD with random E/W hands and single dummy leads (I remember reading somewhere that the opening lead was statistically the single play with the largest deviation from DD-optimality, which sounds reasonable), but this would require writing down all the information given in each auction -- a bit too much work for me right now.

[rbforster]

I can do the simulations (DD with random E/W hands) but I think this would miss an important point, which is information leaked in the auction. What would be more convincing would be DD with random E/W hands and single dummy leads (I remember reading somewhere that the opening lead was statistically the single play with the largest deviation from DD-optimality, which sounds reasonable), but this would require writing down all the information given in each auction -- a bit too much work for me right now.

Antony - I think people would be interested to see your simulation results, even with the caveats you mention (DD with random E/W). Whatever you find easiest to sim up would still be appreciated and valuable. Those who want to make slight adjustments based on the hand in question (if it has two way finesses or whatever) can do that for themselves.

[straube]

Antony - I think people would be interested to see your simulation results, even with the caveats you mention (DD with random E/W). Whatever you find easiest to sim up would still be appreciated and valuable. Those who want to make slight adjustments based on the hand in question (if it has two way finesses or whatever) can do that for themselves.

 

I'm somewhat interested in simulated results, too, but I'd like to see us get through a hundred or so deals and then have a conversation what to do with them. It's hard enough to avoid resulting after looking at both hands without extra pressure of trying to reach the par contract. I think everyone has the right idea here of trying to follow their system agreements and let chips fall where they may. Simulated results can help our personal assessment but I'd like this to stay more like a study.

[antonylee]

OK, I won't post anything for now then.

[rbforster]

I'm somewhat interested in simulated results, too, but I'd like to see us get through a hundred or so deals and then have a conversation what to do with them. It's hard enough to avoid resulting after looking at both hands without extra pressure of trying to reach the par contract. I think everyone has the right idea here of trying to follow their system agreements and let chips fall where they may. Simulated results can help our personal assessment but I'd like this to stay more like a study.

It's your study/contest so I'm happy to go along with your preference, but most of the time people can see both hands and tell what the best contract would be (i.e. is slam on, NT vs 5-2 major game, which part score, etc). I think in a format like these forums where you can't hide the information perfectly, you just have to trust people to try to bid their system accurately.

 

That said, there are some deals where the layout is complex and its not clear what the best contract might be (like #20). I think adding some sim results after everyone has had a chance to bid them would be a nice followup to the discussion.

[akhare]

It's your study/contest so I'm happy to go along with your preference, but most of the time people can see both hands and tell what the best contract would be (i.e. is slam on, NT vs 5-2 major game, which part score, etc). I think in a format like these forums where you can't hide the information perfectly, you just have to trust people to try to bid their system accurately.

 

That said, there are some deals where the layout is complex and its not clear what the best contract might be (like #20). I think adding some sim results after everyone has had a chance to bid them would be a nice followup to the discussion.

+1 -- the DD data would be nice as a reference point and can be used as supplementary information. On the related note, see this regarding deal 20.

[straube]

I'm happy to go along with the group consensus. If Antony or whoever is running sims wants to send me the results for different hands, I can periodically add them to the first post on each deal. That's just one idea anyway. I think I would build some sort of delay into it. I'd just like to not make this a contest...especially one that may influence future results.

[Zelandakh]

It's your study/contest

I hope contributors do not see this as a contest. In my opinion, anyone viewing these hands that way is missing an opportunity.

[straube]

At unfavorable do you stick your neck out with AJ543 K 9864 T93 after a strong club 1C P 1D auction?

[akhare]

At unfavorable do you stick your neck out with AJ543 K 9864 T93 after a strong club 1C P 1D auction?

At that vul., I wouldn't want to come in with that hand after a standard 1♣ - 1♦, let alone after a strong ♣, but that's me.

[straube]

At that vul., I wouldn't want to come in with that hand after a standard 1♣ - 1♦, let alone after a strong ♣, but that's me.

 

Thanks. Me neither.