Another OKbridge player, Craig Chase, later translated the analysis program from Pascal into C, and Matt did the final implementation in the early commercial versions of OKbridge. The explanation below is intended as a brief introduction to how the rating system works. For further details, see the official specification article from 1993. See also the new explanation which is an attempt to show the calculation process through a simple analogy. The rating system should above all tend to reward a player for being a good partner , if possible, rather than rewarding individualistic masterminding.
Bridge is a game of partnership cooperation and communication.
The only aspect of the game which is independent of partner's ability is declarer play. And it is far more difficult to bid and defend accurately with a bad partner than with a good one. The worse one's partner is, the more bridge ceases to be a partnership game. Therefore, a player's personal rating should reflect that player's demonstrated ability to play well with any partner, superior or inferior. Calculation Each player's ratings are recalculated once per week, in the same cycle that generates the next week's set of duplicate boards.