  The Kruskal Count is a card trick invented by Martin J. Kruskal in which a
magician "guesses" a card selected by a subject according to a certain counting
procedure. With high probability the magician can correctly "guess" the card.
The success of the trick is based on a mathematical principle related to
coupling methods for Markov chains. This paper analyzes in detail two
simplified variants of the trick and estimates the probability of success. The
model predictions are compared with simulation data for several variants of the
actual trick.
