It's difficult to describe precisely how GIB defends. It doesn't use rules and guidelines, like humans often do. It simulates hands based on the auction, using double dummy analysis to determine the average result of each defensive play, and chooses the one with the best average. Sometimes this simulation comes up with the same choice that a human would make (there's a good reason for some of the guidelines -- they actually work well), but not always (some of our rules of thumb have become popular simply because they're easy to remember and "good enough"). When it has a choice of equivalent cards, it will choose based on leading and signalling conventions. GIB doesn't interpret your signals or make many inferences from the play, it uses simulations based on the auction. However, it's usually able to figure out that when you lead an honor, it's part of a sequence. GIB usually leads passively against NT (read the book Winning Notrump Leads to understand why). Don't assume it's leading its longest suit. When you lead, it doesn't assume you're leading your best suit, which is why it doesn't always return the suit like a human would. In suit contracts, GIB's opening lead is frequently a side singleton or doubleton, to try to get a ruff. When it leads a suit bid by the opponents, this is almost always the reason. Read the book Winning Suit Contract Leads for insight on the way GIB leads against suits. If it leads an honor that's part of a sequence, it uses standard honor leads (K from AKx, A from AK doubleton). If it leads from a long suit, it leads 4th best (but see above: it doesn't always lead its long suit). When leading from 3 small, it leads low against both suit and NT contracts. It doesn't use any signals when making discards, it just tries to make safe discards. In a suit contract it will frequently discard from a short suit while it has trumps left. Otherwise, it tends to discard from a long suit that's safe to shorten. When it's following to partner's opening lead, it will usually give an attitude signal: High spot card with an Ace or King High spot card with a Queen behind dummy's Ace or King Low in any other situation Note that it doesn't give count in this situation, so it's hard to know when you can give it a ruff. When it's trying to win the trick in third hand, it will play the lowest of equals. Otherwise, when following suit it usually gives standard count signals (high = even); an exception is when it's forced to play equivalent cards in a doubleton, it will randomize them because of "restricted choice". @@bridgelesson
On Board 6 was W using Truscott/Jordan over the Double? If so, is that a partnership agreement?
It says somewhere in the GIB documentation that they give count and no other signal.
Ooooh. Nice. Thanks.
It's difficult to describe precisely how GIB defends. It doesn't use rules and guidelines, like humans often do. It simulates hands based on the auction, using double dummy analysis to determine the average result of each defensive play, and chooses the one with the best average. Sometimes this simulation comes up with the same choice that a human would make (there's a good reason for some of the guidelines -- they actually work well), but not always (some of our rules of thumb have become popular simply because they're easy to remember and "good enough"). When it has a choice of equivalent cards, it will choose based on leading and signalling conventions.
GIB doesn't interpret your signals or make many inferences from the play, it uses simulations based on the auction. However, it's usually able to figure out that when you lead an honor, it's part of a sequence.
GIB usually leads passively against NT (read the book Winning Notrump Leads to understand why). Don't assume it's leading its longest suit. When you lead, it doesn't assume you're leading your best suit, which is why it doesn't always return the suit like a human would.
In suit contracts, GIB's opening lead is frequently a side singleton or doubleton, to try to get a ruff. When it leads a suit bid by the opponents, this is almost always the reason. Read the book Winning Suit Contract Leads for insight on the way GIB leads against suits.
If it leads an honor that's part of a sequence, it uses standard honor leads (K from AKx, A from AK doubleton). If it leads from a long suit, it leads 4th best (but see above: it doesn't always lead its long suit). When leading from 3 small, it leads low against both suit and NT contracts.
It doesn't use any signals when making discards, it just tries to make safe discards. In a suit contract it will frequently discard from a short suit while it has trumps left. Otherwise, it tends to discard from a long suit that's safe to shorten.
When it's following to partner's opening lead, it will usually give an attitude signal:
High spot card with an Ace or King
High spot card with a Queen behind dummy's Ace or King
Low in any other situation
Note that it doesn't give count in this situation, so it's hard to know when you can give it a ruff.
When it's trying to win the trick in third hand, it will play the lowest of equals. Otherwise, when following suit it usually gives standard count signals (high = even); an exception is when it's forced to play equivalent cards in a doubleton, it will randomize them because of "restricted choice".
@@bridgelesson
This was pasted from BBO
@@robertschachter5052 thanks
2C
double
1c
Small
3 nt
CA K and J
DJ and CJ
1H
5H
1D
Small