This project explores a classic problem in understanding probability. Turtles repeatedly play the 'three-doors' game (otherwise known as the 'Monty Hall puzzle', or 'goats-and-cars'), in which they must choose one of three doors. A prize is behind one door, something worthless behind the other two. After selecting, one of the remaining doors is opened, and they are offered a choice: stick with the first door picked, or switch to the other, unopened door. Here, each turtle has a percentage chance (indicated by color) of how often it will switch to the other door. Turtles race against each other, only advancing if they win the prize each round.

For detailed instructions on using the program, take a look at the info window from the Three Doors model.