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The IAC Café / Re: The online NABC. Practice and then the tourney
« Last post by ggriffin0 on Yesterday at 10:24:46 PM »
So a few things left unsaid from my earlier post on the topic. Do we really think the bot is trying to push part score up a level knowing game isn’t there at those vulnerabilities (think possible sacrifice).

A caution: changing the vulnerability to disadvantage or both red changes the logic.

A second caution: if real opps the rationale provided is worth less than one gummy bear. Opponents can use this (I would) to push the bidding to 4!s just to X thereby creating an opportunity.
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The IAC Café / Re: The online NABC. Practice and then the tourney
« Last post by kenberg on Yesterday at 04:22:43 PM »
I agree that the feature of interest is that responder, for the auction so far, could have a 6 count and in fact  he has a 12 count. A good 12 count, no wasted values in hearts, top cards in clubs, fitting cards in diamonds. Given the auction so far, responder is looking at a very good hand.

4 !S makes even with the 4-2 split, and in fact I was planning on playing safely for 10 tricks if E had ducked the second spade. I am thinking though that responder, if he decides to bid a game, might choose 5 !D. It might require less good fortune than 4 !S. As the cards lie there are 12 tricks in diamonds, giving us a little room for misfortune if we are playing game 5 !D.  Bidding 5 !D  depends on him reasoning that surely I must have good diamonds for that 3 !S call.   That might be asking too much of either a human or a bot. 5 !D making 6 would have been 620, just like 4 !S making 4.

Anyway, +200 was above average. It's not often that 3 !S making 5 is a good result, but it's a hard hand to bid, I think.


Bottom line is that I agree with Grant that responder is the one sitting with more values than he has yet shown so it is up to him to get us there if we are to be in game. Which doesn't quite mean that I would have bid game if I were responder. I would be tempted I think.

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The IAC Café / Re: The online NABC. Practice and then the tourney
« Last post by ggriffin0 on Yesterday at 03:18:10 PM »
Looking at the auction and understanding Ken is opener and the bot is responder. I think the real issue here is that the bot needs to take some action. Why? My partner has an opener, I have an opener. Let’s deconstruct what we know about the hands fitting together now we know about the relative strength. We know responder has 4x in spades otherwise we would see 3!s or 4!s being plunked down. Opener can not see anything yet.

So let’s switch back over to what we know if we were sitting in responder’s seat. Back to this idea of relative strength. As responder we know that partner has xxx in spades and must have their opening suit. And potentially the other minor as well. Looking at the bidding we know opponents do NOT have game values, BUT have likely found their suit (hearts) and are distributional. Ok...that sounds benign at the outset but should we consider that something significantly nefarious is going on? If we take that route then the 2H seems normal and the 3H is not. So what are the opponents trying to obfuscate? They certainly are not bidding game and likely know your partnership is on the moysian in spades.

Hmmm. I think we are onto something here. Is this a gambit to cause you to make a decision? Sell out to 4 spades (again they are distributional, you and your partner are likely to be too in hearts). So shoot for 4 spades (I am personally not a fan, distributionally thinking probability suggests the split is not the 40% 3-3) or search for the minor fit. I leave that decision up to u as well as how to get there.

All this said, I 100% agree with augmenting one’s bidding to mesh better with the bots.
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The IAC Café / Re: The online NABC. Practice and then the tourney
« Last post by kenberg on Yesterday at 02:15:49 PM »
"It could be interesting to discuss some of the hands that come up."

For example:
Red against white you have the following auction
  P      1 !D       P     1 !S
2 !H     X      3 !H     P
  P      3 !S

What do we make of 3 !S?  The double of 2 !H showed three spades,  the 1 !S could be on four cards to the 8 for all anyone knows,  still opener is bidding 3 !S.  What's up?  I was the crazy 3 !S bidder if that fact helps any.

Here is the full hand.

http://tinyurl.com/y97tu2ll

Note: The link shows me as responder, but during the bidding I was opener. The software switches us for the play if the human would be the dummy.

The hand is maybe a bit tough to bid, and maybe it's a bit lucky. Both 4 !S and 6 !D are there for the taking. We got an above average score for +200 when Gib, a bit surprisingly,  slipped on defense.  Few found the game, let alone the diamond slam.


I'm not at all sure who should have done what in the bidding.  I do think that my 3 !S bid should show that I can play  4 !D , or perhaps 4 !C, if indeed responder has xxxx in spades. I am claiming this is more a matter of logic than of convention. I am known to have only three spades, responder has not yet shown either good values or a fifth spade. Still I trot out a 3 !S call. I must have a fall back option.  Or maybe AKx in spades, I suppose.  But with AKx I would still need a source of tricks in a side suit.

Anyone is welcome to weigh in here with their thoughts.

jdonn, in his lecture yesterday, talked a bit about adjustments to bidding and play when pard and opps are bots. Yes, I make some, but not many.  I treat my bots as if they were human. They might or might not see that as a compliment.






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IAC Teaching Sessions / Special Sessions by Grant Griffin
« Last post by ggriffin0 on Yesterday at 01:30:04 PM »
Thank you all who have participated and attended my lessons on various subjects. Having passed my second year -into the third- volunteering here for IAC, I will most likely be returning to a weak nt system, beginning with basic before moving into highly modified. Although beforehand, the next series will be on preparing for a national event. This is likely to be heavily focused on what psychology literature on the cognitive and emotional side of things has to offer followed by the second half of each lesson (bidding, declaring, and defense). That is what is upcoming...

BUT...a little known fact. I typically conduct session series based on IAC members inquiry. So here is your moment...Is there a topic that you have been wanting and just can’t find? If so, let me know...
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The IAC Café / The online NABC. Practice and then the tourney
« Last post by kenberg on February 17, 2018, 03:31:28 PM »
In case you missed the announcements,  acbl/bbo has this online robot game with practice tourneys.

See  http://webutil.bridgebase.com/v2/news_fetch.php?id=4521

The practice tourney today (Feb 17) was free, I think they all are.  12 boards, playing with the bots. There is an online lecture today by jdonn at 1 est. The actual tourney in March costs $40.  You do have to belong to the acbl, that appears to be for the practice as well as the full tourney. Ah, they have an update, the practice tourney today is open to all.

The bots come in for a lot of criticism but  these are the strong bots, I guess the same as the ones you pay a dollar a day for if you rent them. At any rate, I just played the Saturday 12 board practice tourney and  as near as I can see the mistakes were mine, not the bots. They did nothing bizarre, I like to think I didn't either, some good results, some not so good, just as it is when playing with humans.

It could be interesting to discuss some of the hands that come up.

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IAC vs World TM's / TM #2 Signups
« Last post by ggriffin0 on February 12, 2018, 12:52:52 AM »
This has been a long time in coming.

Ok. Please read this very closely.

The dates are:

TM #2 (3/8 @2PM EDT)

* Due to lack of interest by IAC members to participate, we have reduced the number of scheduled matches down to one. Thank you to the mentors and opponents that have volunteered their time and all those who participated in the first :).

BEFORE SIGNING UP READ THIS!

1) You must have signed up via the survey sent out in late October. Signups will follow the first come-first serve for that October survey. I am not sharing the list as it is private and contains sensitive information, but I will certainly cross-reference for fairness.

2) If you are an IAC member. Sign up with your BBO username followed by "-I." For example, jsmith would signup to play using "jsmith-I." We will continue to try to match based on availability and system as specified in the earlier survey.

3) If you are a teacher/mentor and are available those times. Please signup using your BBO username followed by "-T." For example, jsmith would signup to play using "jsmith-T."

4) We NEED ex/WC opponents. We will vet the opponents through a simple process, but if you know of an opposing team of 4 players please send them a link to this post. Perhaps there is a group at your local club who would volunteer for this worthy cause or a Team of Exp/WC BBO-ers? If so, we would be happy to have them. Opponents please signup with the team captain's BBO username followed by "-O." For example, jsmith would signup to play using "jsmith-O."

Here is the link...https://doodle.com/poll/9sbgv5faf4uy5zrs

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The IAC Café / Re: xyz/2way nmf, some details
« Last post by kenberg on February 06, 2018, 01:25:35 PM »
I have been thinking a bit about an auction on page 6 of the cited notes.

1 !D     1 !H
1NT     2 !C (-> !D)
2 !D     3 !C

The notes say, and I believe Dave said,  that this is an invitational 5-5 in !H and !C.  So it's the standard way, I guess. But is it best? I will take the basic structure as a given. After 2 !C over 1NT opener must bid 2 !D. Responder with a weak hand passes this, any other call is invitational. The forcing sequences all start with 2 !D over 1NT.

I raise the question of what happens when responder, hearing a 1 !D opening, has six clubs and four hearts.


First let's look at a similar but not identical sequence also on page 6:

1 !C     1 !H
1NT     2 !C (-> !D)
2 !D     3 !C

The opening call here is 1 !C  instead of 1 !D. This time the notes say this is invitational with a club fit, but only four hearts to go with the five clubs. 

I don't think the notes mention it, but it is then logical to play that

1 !C     1 !H
1NT     3 !C

is a weak hand with four hearts and five (or more) clubs. Logical because the strong hand would start with 2 !D and the invitational hand would start with 2 !C so what's left is the weak hand.

Now back to 1 !D - 1M - 1NT. Responder can have six clubs and four cards in M. With a strong hand he of course bids 2 !D. But he could also have an invitational hand or he could have a weak hand. If going through 2 !C and then bidding 3 !C shows 5-5, then there is only one call left to show the 6-4. If 1 !D -1M -1NT - 3 !C is an invitational 6-4  then we have no call for the weak 6-4.


Ok, it's maybe not a huge problem, mostly because when we have a weak shapely hand opposite a 12-14 hand the opponents are probably in the auction before we get to bring out any convention.  But still. At least we have to agree on whether 1 !D -M -1NT - 3 !C is a weak 6-4 or an invitational 6-4. I have known people who play it invit and people who have played it weak. Most common is that it is undiscussed.

I was thinking of an alternative. Consider

1 !D     1 !H
1NT     2 !C (-> !D)
2 !D     2 !H

This is an invitational hand with five hearts. If opener has three hearts, nobody cares how many clubs responder has. If opener has two hearts and accepts the invitation with 3NT then there might well be 9 tricks in NT. If opener has two hearts and declines the invitation with 2NT, responder could still bid 3 !C if he has the 5-5 hand.

Responder with the 5-5 bids 3 !C directly over 2 !D according to the notes. My suggestion has him bidding 3 !C also, but doing so only after it is clear that they don't have a heart fit.  This allows us to still play  that a 3 !C call over the forced 2 !D shows long clubs four not five hearts, and invitational values while directly bidding 3 !C over 1NT is the weak hand with four hearts and long clubs.

No doubt bidding theorists have though of this, there are very few things that they haven't thought of, but I don't see what's wrong with it.  Among other things, it means that after 1m-1M-1NT, the call of 2 !C followed by 3 !C shows fitting clubs and four hearts regardless of whether m is !C or !D. In the notes, the 3 !C shows four !H if the opening m is clubs and five !H if the opening m is !D. This is a memory challenge for a sequence that doesn't come up very often.

Being retired means having enough time to worry about such things. It's probably not at the top of anyone's list.

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IAC Teaching Sessions / Re: Special Squeeze lesson by Angel Blue
« Last post by Curls77 on February 04, 2018, 09:27:39 PM »
Link is :  https://goo.gl/Rc7KkQ

Please bookmark it, as it's youtube video chanel, created by Roger and Charlene where they will post all sessions that are recorded.
I'd also suggest that a TY bbo-mail to RogerPfi and GG_Bridge, that do so much for IAC, within aaBrigde, and also these recordings, as well as OCP classes should at least be thanked with big hug :)
TY both!  !H


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The IAC Café / xyz/2way nmf, some details
« Last post by kenberg on January 31, 2018, 03:46:27 PM »
In Dave Greenough's lesson yesterday there was some discussion of xyz after 1 !D - 1 !S - 1NT.  I have a reference with details and  examples for those who are interested.  As near as I can tell, after 1x-1y-1NT, 2 way new minor is simply an alternate name for the broader convention xyz.
I believe this write-up is in total agreement with what Dave said.

http://www.lajollabridge.com/LJUnit/Education/2-WayNewMinorForcing.pdf


The link has a hand on page 6 similar to the one that came up in the lesson. After 1 !D - 1  !H - 1NT,  responder has an 11 count and five clubs. He can simply raise to 2NT natural and invitational.  But how about first bidding 2 !C,  this forces opener to bid 2 !D, and then bidding 2NT?  What should this be? Dave explained that one of these ways shows clubs, the other doesn't, and different people play it differently as to which shows five clubs. It's not something that arises frequently so I think simple is good, and the following seems simple (to me): A direct raise of 1NT to 2NT is invitational with the expectation that partner will pass or bid 3NT. Going through the 2 !C - 2 !D - 2NT route is also an invitation to 3NT but suggests that if opener does not want to play in game then he might, on some holdings,  want to get out in 3 !C.

The hand in the lesson began 1 !D - 1 !S - 1NT but again responder had five clubs and an 11 count.

This matches with a general approach that I like: A direct bid means what it sounds like it means, a longer sequence suggests options other than the obvious. So here, a direct 2NT says let's play in NT at the 2 or 3 level, going through the relay says maybe we play in 2NT, maybe 3NT, or, in some cases, maybe 3 !C.

The write-up suggests just skipping this and raising to 2NT. Ok by me.

As mentioned, the write-up says what Dave said. So why am I bothering? Well, if someone wanted to play this, he could suggest to his partner: Let's play it this way. A while back I was playing with someone and we agreed to do exactly that. It's a pretty decent convention and, with many (but still not all) details written down, we had no mishaps. Well, at least not any caused by confusion over the meaning of a sequence.


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