Backgammon Thorp Count


A formula for help making doubling decisions in  pure race situations in backgammon games. It enhances the basic pip count by accounting  for elements of checker distribution.  It was devised by Dr. Edward O. Thorp. 


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.


Dr. 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.



This Dr. Thorp is the same who wrote the 1960’s best selling book on Blackjack “Beat the Dealer” made Blackjack most popular casino game in the U.S.


See post by Simon Woodhead.  For a comparison with other methods, see article by Tom Keith.