Wbridge5 is a prominent bridge program. Wbridge5 has been world champion of the bridge programs in 2005, 2007, 2008, 2015, and 2016. Besides excellent playing, this program also employs a dedicated bidding system. This book is a technical report of that system as Wbridge5 5.12 bids it. There is also a collation in Full Disclosure format.
The topic of this book is bidding. Card play is left out except for the opening lead and defensive signals, which are agreements between partners like the bidding.
Wbridge5 has a 2/1 bidding system with French flavors, as it originates from France. Some French conventions greatly improve bidding structure from the American, so Wbridge5 incorporates them. Others not so profitable are not included in Wbridge5.
Each chapter describes what Wbridge5 bids, verified by probing the program itself over the Table Manager protocol. The probe harness and its data are in the source repository. The chapters also compare the probes with the 2011 writeup, the author’s 2009–2011 Chinese writeup of the system: Wbridge5 humanized, with improvements for human players by the principle of useful space. Where the two differ, the probe wins. Rules from it and other older writeups that 5.12 does not play are archived outside this book as optional agreements.
Wbridge5 sits South in every probe. The harness plays the other three seats from a fixed auction and deals South random hands under constraints on shape and HCP. The dealer is set so that South calls right after that auction, whose first call is thus in 1st seat. South opens in 1st seat unless the auction starts with passes, and its direct overcalls are in 2nd seat. Nobody is vulnerable unless a chapter says otherwise, and the opponents play Wbridge5’s own system unless a chapter names SEF or SAYC. An auction usually gets 300 boards, up to 1000 for rare calls. Wbridge5 makes South’s earlier calls in the auction itself, and a board where it strays from the script is dropped. A range in this book is what Wbridge5 bid on the boards kept, so a rare hand at its edge may bid otherwise.
Notation
This book follows Strawberry Polish Club for bidding notation and punctuation in tables and prose. Hand evaluation is Wbridge5’s own, described in its chapter.
References
- Yves Costel. Wbridge5
- Chen-Pang He. Wbr5.bss
- Chen-Pang He. Strawberry Polish Club
- Thomas Andrews. Thomas’s Bridge Fantasia
License
The source code is hosted on GitHub. Feel free to share or improve this book. The content is released under CC BY-SA 4.0. The source code is released under GPLv3+.