[goffster]

Near the end robot can take 10 tricks, chooses to go down instead. I thought even non-advanced robots knew enough to take their tricks.

https://www.bridgeba...dt%7Cpc%7Cd4%7C

[smerriman]

Was this MPs or IMPs? Obviously, at IMPs, it would be a mistake.

But at MPs, GIB will go for the club finesse every time. Of the 15 possible layouts after trick 9, playing on clubs gains on 10 of them (where West has the club ace), ties in 1 (when East had ace to 3 clubs) and only loses in 4 (when East had ace to 4).

[goffster]

 smerriman, on 2020-October-09, 01:43, said:

Was this MPs or IMPs? Obviously, at IMPs, it would be a mistake.

But at MPs, GIB will go for the club finesse every time. Of the 15 possible layouts after trick 9, playing on clubs gains on 10 of them (where West has the club ace), ties in 1 (when East had ace to 3 clubs) and only loses in 4 (when East had ace to 4).

This was IMPS

[pescetom]

 smerriman, on 2020-October-09, 01:43, said:

Was this MPs or IMPs? Obviously, at IMPs, it would be a mistake.

But at MPs, GIB will go for the club finesse every time. Of the 15 possible layouts after trick 9, playing on clubs gains on 10 of them (where West has the club ace), ties in 1 (when East had ace to 3 clubs) and only loses in 4 (when East had ace to 4).

AFAIK (from reading here, I very rarely play with GIB) GIB makes no distinction between MP and IMPs but is more adapt to the former.
I can understand the club finesse, but not why it failed to go for the diamonds finesse at trick 6.

[johnu]

 smerriman, on 2020-October-09, 01:43, said:

Was this MPs or IMPs? Obviously, at IMPs, it would be a mistake.

But at MPs, GIB will go for the club finesse every time. Of the 15 possible layouts after trick 9, playing on clubs gains on 10 of them (where West has the club ace), ties in 1 (when East had ace to 3 clubs) and only loses in 4 (when East had ace to 4).

If you look at the first 5 or 6 tricks you should be easily able to tell that this was either played by GIB or a very beginner player.

What is the percentage of playing the last trump (♥3) when there are no trumps out and you can only beat the 2 which was already played?

At trick 8, you have 2 top spades, 3 diamond tricks, 4 trump tricks, and a spade ruff if you take all your tricks. If GIB had not needlessly played the last trump, it could play ♦K and a diamond endplaying East. If East had a spade left, South could ruff and lead a club winning if West had ♣A.

[smerriman]

 johnu, on 2020-October-10, 13:29, said:

If you look at the first 5 or 6 tricks you should be easily able to tell that this was either played by GIB or a very beginner player.

Well, you can tell that by looking at the username before the first trick Obviously, GIB's play in general is bad, I doubt anyone denies that. The question was figuring out a possible reason why it goes down.

[johnu]

 smerriman, on 2020-October-10, 18:26, said:

Well, you can tell that by looking at the username before the first trick Obviously, GIB's play in general is bad, I doubt anyone denies that. The question was figuring out a possible reason why it goes down.

If you can figure out why GIB would play the last trump, you should apply to be a GIB programmer because I doubt any of the current programmers know.

And as I have posted, the club finesse is wrong, as well as the throw-in. Just go back a trick and don't play a trump and you can do an end play as well as take the club finesse.

[smerriman]

 johnu, on 2020-October-10, 23:14, said:

If you can figure out why GIB would play the last trump, you should apply to be a GIB programmer because I doubt any of the current programmers know.

Really? Unless I'm missing something, that part is pretty obvious and has been posted about many times in the forum (you've even posted about it yourself). While playing the trump is obviously stupid, on every layout of the opponent's cards, playing the trump will result in +1 double dummy. Playing the diamond won't (if East has Axx of clubs). Basic GIB isn't distinguishing plays that require future knowledge from plays which don't.

That type of logic is what the GIBson part of the advanced robot is meant to fix.

[johnu]

I misread the OP's post and thought he was talking about advanced robots. When it comes to basic GIBs, BBO has said they don't know why they make some of the mistakes they make, and they have no plans to fix them at any time in the future. Basic GIBs are an end of the line product with no future.

[nige1]

goffster 'Near the end robot can take 10 tricks, chooses to go down instead. I thought even non-advanced robots knew enough to take their tricks.'
+++++++++++++++++++

At then end, Gib can play ♦Kx ensuring the contract and making an overtrick as the cards lie.
Given how hard it seems to fix GIB bugs, why won't BBO replace it?

---

[pescetom]

 nige1, on 2020-October-11, 22:26, said:

Given how hard it seems to fix GIB bugs, why won't BBO replace it?

I imagine that is why they just bought out BridgeBaron (has a robot that places in the top five worldwide).
Although maybe not, they seem convinced that the ship is unsinkable as it is.

[neals384]

 smerriman, on 2020-October-09, 01:43, said:

Was this MPs or IMPs? Obviously, at IMPs, it would be a mistake.

But at MPs, GIB will go for the club finesse every time. Of the 15 possible layouts after trick 9, playing on clubs gains on 10 of them (where West has the club ace), ties in 1 (when East had ace to 3 clubs) and only loses in 4 (when East had ace to 4).

Not sure I quite follow. After West shows out on the second D, East is marked with 2 diamonds, so cannot hold 3 or 4 clubs. Still 15 combination, 10 of which generate an overtrick, plus 2 ties (singleton A or AQ of clubs) and 3 losses.

[smerriman]

 neals384, on 2020-November-10, 09:40, said:

Not sure I quite follow. After West shows out on the second D, East is marked with 2 diamonds, so cannot hold 3 or 4 clubs. Still 15 combination, 10 of which generate an overtrick, plus 2 ties (singleton A or AQ of clubs) and 3 losses.

I was referring to the original holdings, not the remaining holdings.

East starting with Axx is not a tie (even though it says it is double dummy), since you don't know this and would still be playing the king of clubs.