smerriman

There is no hand that matches South's bidding. The closest you can get to a 3NT bid shape-wise, maybe the main thing it locks in, is probably: [hv=http://www.bridgebase.com/tools/handviewer.html?s=SQJ62HA72DAK42CKQ&w=S53HKT954DQT95C53&n=SAK8HQJ863DCJ7642&e=ST974HDJ8763CAT98&d=n&v=o&b=1&a=1HP3NP4HP5DP5HP5SP6HP6NPPDPPP&p=C5C2CTCKCQC3C4CAC8D2DTCJSAS7S2S5SKS4S6S3S8STSQH4SJH5H3S9DAD5H6D3DKDQ]400|300[/hv] Lo and behold, on that layout, dropping the ♦Q is the best play. I don't know how it distinguishes one impossible hand from another in simulations, but the way it assumes you have your bid causes virtually all play bugs and really needs to be fixed. But either they don't consider it a bug, or don't know how to fix it. Probably both.

That sounds fair.

Actually, it appears olegru failed to finish the challenge, with the last 5 boards being unplayed. Olegru - can you explain?

GIB being broken with off-shape takeout doubles is probably the oldest bug on the list. (4 spades comes from the takeout double; the descriptions can then never recover).

Thanks - hadn't extended the formulas to account for 2 more columns than the last event.

http://webutil.bridgebase.com/v2/tview.php?t=ARDCHALLENGE:1bd9924f.aa5e.11e8.83a5.0cc47a39aeb4-1535418180&u=smerriman 8-8 vs mlbridge http://webutil.bridgebase.com/v2/tview.php?t=ARDCHALLENGE:0aa1be0a.abd1.11e8.83a5.0cc47a39aeb4-1535577494&u=smerriman 8-8 vs broze http://webutil.bridgebase.com/v2/tview.php?t=ARDCHALLENGE:8d930255.aa9d.11e8.83a5.0cc47a39aeb4-1535445429&u=smerriman 6.5-9.5 vs gordontd (That last one was embarrassing. Played too late at night - I repeatedly forgot which cards were winners :/ )

To be specific, double dummy it can never cost to cash the ♦A at trick 2, because if the ♣K is onside, it can finesse clubs at trick 3. The algorithm that uses logic like "but you won't know what to do at trick 3" and plans accordingly doesn't kick in until trick 3 sadly.

26 entrants this time so (after temporarily considering adding GIB as a 27th, given we now have challenge-a-robot ;) ) I've just gone with 2 groups of 13. Groups are assigned here: https://www.dropbox.com/s/a7bqnhhfe91huki/Event%2014.xlsx?dl=0 Complete one 16 board, MP, best hand friend challenge against everyone in your group. Do not check the Advanced Robots checkbox - but all challenges will automatically be upgraded to advanced robots. (At least) one player should report the scores of each challenge here by pasting a results URL - you can get the URL via My BBO - Recent Tournaments - Results - Open in new window. The top five in each group will combine into a second round robin. Scores will be carried forward, but to give everyone a chance of revenge for earlier matches, this round robin will be over 32 boards (ie another 16 against your 4 group members, and 32 against the other 5). The top four of the second round robin will compete head to head in a semifinal and final (1 vs 4, 2 vs 3). I will set a tentative deadline of Sunday September, 23rd, 11:59pm EST to aim for - 4 weeks for 12 matches = 3 matches a week, as things went pretty smoothly last time - but can push this back if people are struggling time wise. To avoid someone being sent all of their challenges immediately, start by challenging those just above/below you in the group, and steadily go up and down from there. Advanced robots have been assigned, so you can start now. Ties will be broken by total matchpoints between tied players. If still tied, total matchpoints against higher ranked players. If still tied, a playoff.

What do you bid with invitational hands?

How can there be any option but pass?

I have considered Swiss, but I think it actually works pretty poorly for this type of event. - Everybody getting to play to the end is actually a disadvantage, not an advantage. Players lower down the rankings after the first couple of rounds have very little motivation to play, especially 64 boards (and not doing so, or not playing to the best of your ability, can heavily influence the results for others). - You only get to play a small number of opponents, which isn't as enjoyable, and (especially with the bonus you mention) a single loss is probably enough to eliminate you, making it heavily dependent on the luck of the draw (and probably no better than a straight knockout). - You don't get the excitement of reaching / winning the last knockout rounds; in fact often with a Swiss the final round is either unimportant (someone has too big a lead) or feels somewhat unfair (leading by a small margin going into the last round is usually a disadvantage as its puts you against better opponents - leading to the "Swiss Gambit" where it's better to perform worse early on). - And lastly, figuring out the draw is pretty complex - not as simple as the method you mentioned (which as you proceed down the table, would quickly lead to someone having already played everyone lower than them). Specialised software is needed to determine the matchups in the fairest possible way. Swiss really only works when every placing is important (eg with chess ratings, every game matters even if you don't win the tournament) and there isn't enough time to run a longer competition where you get to meet more opponents. Here it's really all about winning the tournament, and it doesn't really feel like you have with Swiss.

Basic or advanced? I don't think basic robots have anything built in which tells them how to evaluate hands opposite partner's shortage (same issue with splinters). Would hope advanced robots could figure it out though.

Sorry, to clarify, I wasn't meaning a strong/weak suit - just that in the former case, GIB often requires extras to cuebid (Example), while I think the latter comes from the "if no bid matches your hand, choose the closest lie" type logic.

(Sorry, had to recreate the thread as I forgot to make it a public poll. If you were the (only) person to vote in the old thread, please re-vote in this one.) For regulars: This is planned to be the same format as last time, but this will be an MP event. If anyone has suggestions as to changes in numbers of boards (eg a longer round 2), feel free to say - seemed to turn out to be a reasonable timeframe last time. First poll: Vote for your preferred format - format will most votes will be used. Second poll: This will form the list of registrations (choose both if you will play regardless of format) Deadline for registrations is Thursday August 23rd, 11:59pm EST. The event will start shortly afterwards. For anyone who has not participated before: This is a forum event based on friend challenges. You will be playing challenges against other members in a round robin / knockout format, with an expectation of around 3 16-board challenges a week. No prizes, just fun. To prove you are capable of creating/accepting challenges, if you have never played in a challenge event before, send me an 8-board challenge in your preferred format. I will accept promptly - you must complete the challenge before expiry to prove you are capable of participating. (If you've competed in any previous event, voting in the poll suffices).

'Unsupported' definitely sums up the OP.

I think this really comes back to an idea floated in the past of being able to create your own multi-player challenges. Which would be excellent.

GIB is meant to bid first round controls (and when the description says ace, that could mean a void). However, it doesn't really work: - Often the descriptions say a control in another suit is denied, even though there was no way of showing that control because bidding that suit earlier would have been natural - Often GIB skips a suit because it thinks it is too weak, vs not having a control (which then leads to future bids saying it didn't have the ace it skipped, etc) - Occasionally, as in the situation you mentioned, GIB cuebids a suit it shouldn't because it thinks it is too strong for any other bid - And usually, when you cuebid to pinpoint a weakness, GIB has no idea what that means and jumps straight to slam / Blackwood despite two quick losers in the problem suit. Though that often fools the opponents into not leading it. So yeah, witih GIB it's probably safest to ignore cuebidding and bid 4NT when you shouldn't or just jump to slam and hope.

I suspect they might be referring to passes with GIB. While you can hover over your own passes, you don't know what others mean (and the descriptions of your own often don't say much). But that's probably more to do with pass being a catch-all that can't be described in most situations.

Ignore my crazy bidding - this was Robot Reward, where you tend to want partner to be declarer always - but: [hv=http://www.bridgebase.com/tools/handviewer.html?sn=smerriman&s=SKQ9HJ985DA93CA95&wn=Robot&w=SAJ43HKQ2D8642C42&nn=Robot&n=ST876HT64DQ5CQT63&en=Robot&e=S52HA73DKJT7CKJ87&d=s&v=n&b=15&a=PPP1D(Minor%20suit%20opening%20--%203+%20%21D%3B%2011-21%20HCP%3B%2012-22%20total%20points)D(Takeout%20double%20--%203-5%20%21C%3B%202-%20%21D%3B%203-4%20%21H%3B)R(4-%20%21D%3B%2010-11%20HCP%3B%2012-%20total%20points%3B%20opponents%20cannot%20play%20undoubled%20below%202N)1S(Length%20--%204+%20%21S%3B%2011-%20HCP%3B%2012-%20total%20points)PPD(Penalty%20--%204-%20%21D%3B%204+%20%21S%3B%2010-11%20HCP%3B%2012-%20total%20points%3B%20opponents%20cannot%20play%20undoubled%20below%202N)2C(4+%20%21C%3B%204+%20%21S%3B%2011-%20HCP%3B%2012-%20total%20points)PPD(Penalty%20--%203+%20%21C%3B%204-%20%21D%3B%204+%20%21S%3B%2010-11%20HCP%3B%2012-%20total%20points%3B%20opponents%20cannot%20play%20undoubled%20below%202N)PP2S(3-5%20%21C%3B%202-%20%21D%3B%203-4%20%21H%3B%204%20%21S%3B%2011-%20HCP%3B%2012)PPP&p=S5SKS4STC5C4CTCJS2S9SJS7SAS8H3SQD4DQDKDACAC2C6C7H9H2HTHADJD3D2D5CKC9D8C3DTD9D6S6H4H7H5HQS3H6C8HJHKCQD7H8]400|300[/hv] After redoubling, ensuring the opponents can't play undoubled below 2N, and making a penalty double of 1♠.. both GIBs are happy to pass out 2♠ undoubled. This isn't just an advanced robot issue. With basic robots, North doesn't bid 2♣, but if I force a 2♣ bid.. both opponents pass out 2♣ undoubled. This is on top of the usual issues where after I make a redouble suggesting I want to penalise the opponents, partner often butts in with bids rather than checking if I want to penalise first.

If basic GIB - with no simulations - often has 8 HCP when it says it should have 9 HCP, then I agree, the description is incorrect and should be updated. If it is only advanced GIB which does this, then the description should not be updated (and it fact it might be logically impossible to update). Why? Because the bid has been with the knowledge that you will assume he has 9 HCP and respond accordingly. If the bid is defined as 8-9 HCP, then that will result in you having to accept less often. That in turn will probably result in GIB no longer inviting with 8 HCP. You'll then complain that GIB always has 9 points despite advertising 8-9! While there are innumerous GIB bugs, I would rather be mislead to get to the right spot than bidding by the book - which is just what Basic robots do, so you could always use them. Unless you're talking about tournaments, in which case I think you'll be outnumbered by your opponents' preferences. Perhaps BBO could let you choose between the two.

KQ in partner's suit is only really huge if partner has the Ace of diamonds. Change Ace of diamonds into a low diamond and a club into the Ace of clubs and game again isn't great. So I can't imagine why 4♠ would ever be better than 3♦ (given South should have accepted with the Ace of diamonds, otherwise what was the point). Edit - I'm probably wrong, I guess all you need is the diamond jack..

Anyone know the stats on this? I would agree if you were opening 1 of a minor - if partner can't respond, it's almost guaranteed someone will be able to overcall in a major. Assume partner can't respond. Holding 4 spades yourself, it's unlikely anyone will be overcalling a spade, and you'd expect each opponent to have about 8-10 points. Unless I'm missing something, it seems you'll be passed out every time unless 4th seat manages to have good enough clubs and points to balance 2♣. Is that really a good chance / a small risk?

Assuming you mean 38%, that doesn't (necessarily) mean you should bid game instead of a game try. It means bidding game is better than passing. If you mean you expect to make game 38% of the time opposite a hand which can't accept a game try, then that's fair enough.

You are entitled to an accurate explanation of how the partner of the bidder understands the bid. The bidder themselves is perfectly entitled to make any bid they like.