Integration by me

Then you will know the truth, and the truth will set you free.

General understandings

Wbridge5 is a closed-source program, so some mechanisms are still unknown. Moreover, this is a bidding book for humans, who cannot run millions of simulations while bidding. Therefore, there must be some adjustments from original methods.

Notations

4 refers to a bid or a contract. “4 hearts” means 4 cards of hearts. 4 is a spot card.

Patterns are shown with hyphens, e.g. 5-4-3-1 refers to a hand with a 5-card suit, a 4-card suit, a 3-card suit, and a singleton. Shapes are shown with equal signs, e.g. 5=4=3=1 means 5 spades, 4 hearts, 3 diamonds, and 1 club.

Hand evaluation

Wbridge5 mainly uses point-count system for bidding. One counts only honors for notrump contracts and defensive values, with distribution points combined for suit contracts. The losing trick count helps evaluate distributed hands for suit contracts.

High card points

Ace
4 HCP
King
3 HCP
Queen
2 HCP
Jack
1 HCP

Distribution points

Void
3 points
Singleton
2 points
Doubleton
1 point

HCP refers to high card points. Simply points refers to HCP + distribution points.

Refined honor points

Wbridge5 makes some adjustments for 10s and unguarded honors, but I have not figure out its rules. Luckily, Thomas’s Bridge Fantasia provides precise evaluators friendly to humans.

Binky

Binky is a theoretical evaluator impossible for a human player to use. To obtain Binky points, one looks up an exhaustive table for every pattern and holding. This evaluator is regarded as a reference here.

Fifths

The Fifths evaluator is the perfect evaluator for 3NT. It is good for other notrump contracts too. Its correlation to real notrump tricks is 0.931, near to Binky’s 0.947.

Ace
4.0 HCP
King
2.8 HCP (↓ 0.2)
Queen
1.8 HCP (↓ 0.2)
Jack
1.0 HCP
Ten
0.4 HCP (↑ 0.4)

Bum-rap

The Bum-rap evaluator is good for suit contracts. With distribution points added, its correlation to real tricks is 0.914, near to Binky’s 0.925.

Ace
4.5 points (↑ 1/2)
King
3 points
Queen
1.5 points (↓ 1/2)
Jack
0.75 points (↓ 1/4)
Ten
0.25 points (↑ 1/4)

Additional distribution points

Thomas has not justified these point-adding systems popular in France, but the Wbridge5 program uses them.

Length

Add 1 point for the 6th card and thereafter in every suit.

Fit

While this is not documented in Wbridge5, I believe the program uses it secretly from my observation on its bidding.

The 9th card
1 point
The 10th card
2 points
The 11th card and thereafter
1 point