A
formula devised by Edward O. Thorp for making doubling
decisions in pure
race backgammon games. It is a modification of the basic pip count
which takes into account some elements of checker
distribution.
Each
player's Thorp count is his pip count, plus 2 for each of his checkers still on
the board, minus 1 for each of his occupied home board
points, plus 1 for each checker on his one-point.
Then the player on
roll increases his count by 10 percent if it is more than 30.
Thorp advises:
Double any time your
count does not exceed the opponent's by more than 2;
redouble
any time your count does not exceed opponent's by more than 1;
accept the double if your count does not exceed
doubler's by more than 2.
See
post by Simon Woodhead. For a comparison with other methods, see
article by Tom
Keith.