Play the Prisoner's Dilema Game!

Bryn Mayr College has a website where you can actually play a mini-prisoner's dilema game, it is similar to the game theory exercises we did in class (like the stop/go game).

Each turn, the player and the computer each must choose whether to "compete" or "cooperate" with each other. Each chooses without knowing what the other party will choose. If both choose to cooperate each get 3 "gold coins." If one says to cooperate and the other says compete, then the one who chose compete gets 5 gold coins and the looser gets none. If both say compete each player gets one coin.

After playing this many times, it seems the computer has been programed so that if I choose cooperate the first time, so does the computer, and as long as I continue to select cooperate, so does the computer, so we both just keep getting coins until the program announces a tie. But if I select compete at any point, the computer starts selecting compete sometimes too.