Invented by the German mathematician Ernst Beck in 1956, Beck's Coefficient is a calculated reference number which gives a rough indication of the probability of there being a possible route to Endgame within a set number of moves.

The constant can only be used as a guideline, since the coefficient works on the assumption that line velocities are constant (Chalfont's Hypothesis suggests a coefficient that accounts for line velocities, but is incalculable on standard equipment within any reasonable amount of time), and unless stated otherwise is calculated for a twenty five move limit.

Of course, when MC has been played, Beck's reaches 1.

The formula for the coefficient is rather too complex and cumbersome to explain here, but is available in any modern book on the game.

[JH]