[Bbradley62]

I was entering a Brave New [to me] World by opening 1NT with a 5-card major, but I thought I might try...

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Can we please teach GIB how to use Lebensohl?

[dustinst22]

Hey, the bot kept you out of a bad 4 spades contract

[barmar]

It's not clear whether the problem is that it doesn't know how to use Lebensohl, or just GIB's general problem with making bids that show a stopper when it doesn't actually have one. We've seen it do the same thing in non-Lebensohl contexts.

[Bbradley62]

There are two independent issues: whether he shows a heart stopper and whether he asks about spades.

[georgi]

The continuation showing other major seems to have a bug. It will be fixed in future release.

[pigpenz]

Bbradley62, on 2011-August-29, 12:48, said:

There are two independent issues: whether he shows a heart stopper and whether he asks about spades.

I thought leb covered those two issue
2NT/3♥ showed spades with heart stopper
Direct 3♥ spades without stopper

[Bbradley62]

pigpenz, on 2011-August-29, 19:47, said:

I thought leb covered those two issue
2NT/3♥ showed spades with heart stopper
Direct 3♥ spades without stopper

Yes, 4 spades in each case. And you can see how well GIB followed the convention, which is why I pointed out that GIB both (a) showed a heart stopper, and (b) failed to search for a 4-4 spade fit.

[pigpenz]

Yes I see that, but first thing we usually ask is slow or fast?
Is that on ccard?....you shouldnt have to look!
Though i realize this has nothing to do with any of this, GIB should only be allowed to play yellow card until he learns what he is doing.

[Bbradley62]

georgi, on 2011-August-29, 14:23, said:

The continuation showing other major seems to have a bug. It will be fixed in future release.

GIB Versions 18 and 19 have been released since that last conversation, so is this still slated to be included in a future release?

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[barmar]

Yes, it's corrected in the bidding database. The book bid with that hand is 3♥, but simulations overrode it.

[georgi]

Bbradley62, on 2011-December-13, 22:03, said:

GIB Versions 18 and 19 have been released since that last conversation, so is this still slated to be included in a future release?

Coming update has other fix regarding Lebensohl, but that ♥Qx seems to be the thing which forced GIB to simulated badly and pick X instead of better bids.

These particular values will be reconsidered.

Having Jx or xx is much easier GIB not to make mistake here.

[Bbradley62]

So, with Qx, GIB can't decide whether to bid Stayman with or without a stopper, so it does neither?

[barmar]

The way simulations work during the bidding is that it makes a number of adjustments to its hand: adding a few points, increasing suit qualities, etc. For each adjustment, it finds the book bid that goes with that hand, resulting in a list of bids to consider (the original book bid and these new ones). Then it deals out a bunch of hands and tries to estimate what the eventual result would be (how the auction would continue, and the result of the play at double dummy) if it made each of those bids. Finally, it chooses the one with the highest expected value in the scoring method (IMP, MP, Total Points).

So it's not a matter of not being able to decide. It simply thought it could do better by starting with a double.

Note that despite having 10 HCP, 3NT doesn't make on a ♦ lead.