On Sunday
, March 4,
at 1PM US Eastern Time (7PM Central European Time), we had
a
special 1 hour teaching session with star player
JDonn (Josh Donn).
The topic was MP and Robot strategy, with a focus on working around some known GIB deficiencies. The goal was to help players planning to
play
ACBL's Spring NABC Online Individual.
For the BBOers who were not able to attend the lecture, let's dive into
the review now.
Good morning, or afternoon or evening depending where you are. In
anticipation of the upcoming online NABC event, I thought I would try
something a little different this week. I want to discuss a topic that
would be most helpful to players entering this event, especially those
who are a little less experienced playing with GIB, BBO’s
bridge-playing robot. Before I start, please keep any questions on hold
until I finish in about 30 minutes, then send them along to Diana_eva
or Aurora. They will ask me in front of everyone and I will do my best
to answer.
As anyone who has played regularly with GIB knows, GIB is not a perfect
player. There are holes in its bidding system, and it has a weird style
in certain areas. BBO is regularly working on improving GIB’s bidding
system and judgment, but there is much work to be done. So today, I
want to talk about some of the areas where GIB needs to be improved,
and how the human player can account for them to avoid disasters. All
of the hands I will show came up for actual users.
The first area I want to discuss is limit raises. Here is a hand that
came up recently in actual play for a user. You hold ♠Kxx
♥AJT9x
♦xxx ♣Ax. You open 1
♥, and partner bids 3
♥, a simple limit raise.
What do you do?
Well let me show you the full hand. This is what happened to a player.
As you can see, GIB made a limit raise on a hand that most humans would
recognize is clearly worth a game force. Why did it do this?
There are a few reasons having to do with how GIB counts its points,
that it doesn’t appreciate the extra trump length enough and that it
downgrades the AQ doubleton because of having honors in a short suit.
But "why" it happens is not really my point. Just know that it happens.
So
when your robot
partner makes a
limit raise, in particular one that shows a 9+
card fit, simply accept it no matter what your hand is. If
the user had
done so on this hand, he wouldn’t have missed an easy game.
The second area I want to discuss is "double and bid" hands.
As I think we all know, when an opponent opens the bidding, you might
be too good to make a simple overcall. This is especially likely to
happen when playing in the online NABC event, since the human player is
programmed to have the best hand at the table. In that case, you double
and then bid your longest suit. However, GIB thinks takeout doubles
show support for all of the unbid suits, and it doesn’t change that
assumption even when you bid again to show a big hand. So when you have
a big hand without support for all the unbid suits, it behooves you to
choose a different strategy when playing with GIB.
What different strategy might that be? I would usually recommend just
making a simple overcall,
even on a heavy hand.
Here is an example that
a user sent in. Holding ♠AKJ
♥Jx
♦KQTxxxx ♣A the
bidding went:
And here's the full hand:
Note that on this auction, GIB opponents bid and responded, so partner
probably doesn’t have much anyway. The auction spiraled out of control,
but in particular notice that
GIB
North assumed partner had spade length even
after the "double and bid" which most human would just
take as a good
hand with diamonds.
If south had simply overcalled 3
♦,
he could rebid diamonds
if he chose when the auction came back on the next round, and all would
have been well:
Even if he missed a game, at least he would be plus
instead of being stuck in a ridiculous contract by his partner.
A quick note. If your suit is a major suit instead of a minor suit on a
hand similar
to this one,
you might
just overcall 4 of the major at your first
opportunity. Even if partner assumes it is a weak bid it
is unlikely to
matter, since you don’t often have a slam after an opponent opens the
bidding. That gets you to game, and partner won’t stick you in any
other suit.
So if this were my hand, I would just overcall 4♠ with GIB,
not risk doubling first.
Let me discuss one more thing, a specific auction in fact.
When you open 1
♦
and GIB responds 2♣, or vice versa, the 2♣ bid is marked as being
forcing to game. Warning, that does not match how GIB thinks! GIB will
pass a 3♣ rebid by either player, so either 1
♦ 2♣ 3♣, or 1
♦ 2♣ 2N 3♣. Sorry that what
GIB plays does not match the explanation in this instance, but be
warned. If you don’t want to be dropped in a partscore, then make
another bid.
Here's a real hand. This player learned the hard way, holding ♠Kx
♥Kxx
♦AKxx ♣Jxxx.
So what could
they have done differently? I recommend a 2NT rebid. I think on the
actual hand GIB would have rebid 3NT. Even if GIB did rebid 3♣, the
player could then have rebid 3NT, needing only AK-sixth of clubs and a
major suit lead to make.
Note: you can take advantage of this part of the system holding an
invitational hand with clubs. If GIB bids 2♣ then 3♣, he is
invitational, not game forcing. And likewise, if you are invitational
with clubs and partner opens 1
♦,
you can feel free to respond 2♣ and then bid 3♣ , knowing GIB will pass
if he is minimum.
Don’t be scared that GIB never has what it says it has. The instances I
describe are exceptions, not the norm.
Let me note however, if GIB
makes an unexplainable bid, or something you think is programmed
incorrectly, you can always report to BBO and it will be looked at.
Here is how you send it in. After the hand is finished, click on the My
Results tab on the right of the screen. Click on the hand you want to
send in from the list of hands you have played. Then on the bottom,
click the Options button, mouse over Export Deal, then click Send Robot
Report. You can type a short note about what went wrong, send it in,
and someone at BBO will give it a look.
I hope to see everyone here entering the online NABC event. It starts
tomorrow! It should be a lot of fun, doesn’t cost much money, and gives
away lots of masterpoints. And the best part? You can play at any time
of day while it is ongoing. More information is available on the News
Feed on the BBO home screen. Have fun in your adventures playing with
GIB, and best of luck to everyone.
I will take questions now.
Q1: Are all limit
raises by gib with 4 card support?
A: When it
raises a major suit directly, 1
♥
P 3
♥ or 1♠ P 3♠,
that promises 4+ card support. With 3 card support it starts with 1NT
forcing, like 1♠ P 1NT P 2
♦
P 3♠
Note: With the 3 card limit raise you shouldn't be insanely aggressive,
it usually has a normal hand.
But the 4 card raise I would always accept.
Q2: Can you talk a
bit more about the first hand, where you had a min hand and 8 losers,
do you believe you'll be better off to pass the limit raise or not?
A: I will
circle back around to it.
I am saying that with this hand, or any hand, I would accept the limit
raise. This was an example from actual play, GIB is too good to make a
limit raise but did so anyway.
But if it was a 3 card limit raise, I would pass since I'm minimum.
If you can imagine in your head, switching around dummy's hearts and
clubs
And game is much worse.
Q3: There are
quite a few questions on how gib defends. Does GIB show attitude, or
count on the opening lead? or neither?
A: How GIB
defends is a difficult and sometimes frustrating topic.
Unfortunately neither, GIB doesn't really signal. You have to make your
best play without the help of a useful signal.
Even in real life, when to give an honest signal to help partner, and
when to avoid signalling so you don't help the opponents, is not a
simple topic.
Sorry there isn't a more satisfying answer but GIB doesn't really
signal.
Q4: Follow up on
this. Would GIB fall for a falsecard? Does declarer carding matter?
A: You
should certainly falsecard against GIB because it can't hurt. But
giving false count won't fool GIB, it won't pay attention.
The falsecards you should make are "mandatory" false cards to give a
losing option in the suit.
For example, you have QTx of a suit to the right of dummy, dummy has
A9xx, declarer leads of dummy, you play low, he plays the jack and it
holds. Next declarer lays down the king. You should drop the queen on
this trick, so declarer doesn't know if you have QTx or Qx and might
finesse back into your 10.
GIB can fall for something like that, and if you don't do it you have
no chance.
But as far as giving false count, you can do it if you want, but it
won't help, or hurt.
Q5: Do you open
11-12 point hands?
A: I do.
Remember you have the best hand at the table in these tournaments, so
if you have 11 neither opponent will have more than that. The hand will
usually belong to your side, so open it.
Q6: On defense, GIB
is fond of leading short suits and is very good at getting a ruff on
defense. But when I lead a short suit and my GIB partner gets in, it
often seems reluctant to give me a ruff. Is there some reason for this?
A: Sounds
like bad luck. If you can get a ruff GIB will tend to give it to you.
Not sure what else to say about that. Leading short suits is a good
idea with GIB, since it will assume that is what you are doing most of
the time. So just keep trying.
Q7: GIB makes
passive safe leads vs NT. Does GIB assume my opening leads are the same?
A: I
believe it does, to the extent that it knows the distribution of the
hand.
I can tell you BBO has been swarmed over time by reports from players
complaining that GIB doesn't return their lead. So that suggests GIB is
playing for partner to be making passive leads.
That's why if you can stand to, it's good to adopt that style. Of
course you aren't likely to be defending too often in this event since
you have the best hand, but you never know.
Q8: I seem to get
a LOT of 4-1 trump breaks playing with GIB. Are the deals completely
random?
A: Yes they
are random.
It's the same complaint people make in real life with computer dealt
hands.
The fact is, hands shuffled by people are TOO balanced and even due to
poor shuffling, cards tend to stay together in the same suits.
The hands on the computer are how random hands are supposed to be. You
are getting the expected amount of bad breaks.
Q9: I often try to
make a light balancing bid or double or a bid or double as a passed
hand but it seems like GIB thinks i have full values for this. Does GIB
not take into account that I am a passed hand and/or just balancing?
A: Yeah
balancing is another subject I could have easily discussed today.
Unfortunately, GIB does not have a good concept that balancing actions
are lighter than direct actions. It tends to hang you for balancing. I
recommend avoiding it whenever possible.
That should be fixed down the road, but for now be wary about
balancing, and never on a light hand.
Q10: In a contested
auction where you are bidding a minor .... your P bids 3♦/♣ and you jump to 5♦/♣ to avoid a turned down
invitation why does GIB jump to 6 with an aceless hand?
A: If
partner bids 3
♦ on
some auction, make sure you check the definitions of 4
♦ and 5
♦ before choosing one of
them.
Maybe 4
♦ fits your
hand better even if you want to be in game. Better for GIB to know what
you have and hopefully make the right decision than to hang you because
it thinks you have a better hand.
Q11: Should human
try to beat GIB to blackwood? GIB not the greatest at judging best
final sport after gib uses BWD
A: Sure if
you can simplify the auction and take charge, it's always a good idea
to do so. GIB is ok with blackwood as far as avoiding slam off 2 aces
and bidding
it off 1 ace. Not so good at finding 7 when all the aces are held
though. Luckily grand slams are relatively uncommon.
Q12: And somewhat
related: Cuebids. Both sides are bidding. I want to know if partner has
a stopper in their suit. Does GIB understand a cuebid in this context.
I seem to have very erratic results with this problem.
A: Cuebidding
opponents suit in a competitive auction is another place where you want
to make sure to check the meaning of the bid before making it.
Some places, where humans would usually think the cuebid is asking for
a stopper, GIB thinks your cuebid is
showing a stopper,
so you have to try something else.
Q13: What does GIB
play over partner's preemptive opening? How does it respond?
A: Over
preempts GIB plays fairly simply. A new suit is forcing. 2NT is feature
ask, if GIB has an A/K/Q to show and anything more than a bare minimum,
it will show it.
That's pretty much it.
There used to be a problem when the preemptor would bid blackwood like
2♠ P 2N P 3♠ P 4♠ P 4NT, but that has been fixed.
Ok I think that will be it for today. I hope everyone has fun in the
online ACBL event. Don't forget to sign up today!
Click here for notes from our
previous lectures.