[calm01]

Arigreen - your response to "Passing of a Forcing Bid" included:

"The underlying problem was that 3S did not promise club support, so GIB didn't know that it could fall back by rebidding 4C. When I updated the definition of 3S to promise 4-card club support, the problem went away. Now GIB chooses among 3N and 4C, picking 3N more often than not."

Based on this most helpful reply, it appears the robots seem to mostly honour the coding that lies behind - and corresponds to - the description of each bid made by its partner.

So if the descriptions are not appropriate for the situation, but the corresponding encoding is consistent with the descriptions, it is not the robot making poor bidding judgements but that the the robot is following poor encoding that corresponds to poor descriptions.

This is another of many similar problems but occurs more often than the issue raised in "Passing of a Forcing Bid".

Here is one of many similar examples I could give:

1C pass 1D 1S
X pass pass pass

The robot almost always seems to pass for penalty.

The double is described as "3+C; 2- D 17-21 HCP biddable S ...". If the double means this, the robots pass is not unreasonable.

But the description is possibly not reasonable bridge.

When opening one of a minor when playing a 5-card major system, holding 4 in major is one of the most frequent situations.

Holding 4 of the opponents suit one can - if one wants to - pass, rebid 1NT or 2NT and double with the other major. Trap passing at the one level is rarely useful.

So a more useful meaning for a double in this sort of situation is 4 in other major and better than sub-minimum hand (12+) and either tolerance (2-3) of your partners suit or if not holding tolerance, say 15+ HCP as then we hold the clear balance of points.

A more credible rebid for the actual description given would not be double but be 2NT or 3NT or if unbalanced pass, support partner or rebid clubs or reverse as appropriate.

Fixing the inappropriate description and the encoding that goes with it would stop the robot passing these common and necessary other 4-card major bids for penalties.

This leaves me with a nice 'warm feeling' about the GIB bidding potential.

If the descriptions make bridge sense and the encoding corresponds to the descriptions, the robots could bejave as a good club player or better.

May i suggest that a comprehensive and independent review is undertaken of:

- the bridge sense of the bidding descriptions,
- the correspondence of encoding to the descriptions,
- development of measures of the consequent improvements in robot bidding.

One such measure would be the improving ratio of robot-robot scores in IMPS compared to robit-human scores in IMPS when three robots are at a table.