Exact model

Win rock-paper-scissors

Probability:
33.3%
Odds:
1 to 2
dBan
−3 dBan

A fixed move beats one of an opponent’s three possible moves, ties one, and loses to one.

Calculation

p = 1 beaten opponent move / 3 possible moves = 1/3

Assumptions

The opponent chooses all three moves with equal probability, independently of your fixed move.

Sources

  1. Uniform three-outcome model