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Prisoner's Dilemma

Prisoner's Dilemma
  • Publisher: 82 Inc.
  • Genre: Education
  • Released: 4 Nov, 2010
  • Size: 3.3 MB
  • Price: FREE!
Download on the AppStore Click here to request a review of this app

  • App Store Info


Two suspects are arrested by the police. They are separated and given the option to turn in evidence against each other. If they each maintain their silence, they will both get off with a lighter penalty. However, if one of them turns in evidence while the other stays silent, the defecting suspect will get off scot-free while the silent suspect gets the brunt of the punishment. If you were the prisoner, what would you do? How much do you trust your partner?

This is the model for Prisoner's Dilemma, a classic psychological game adapted for the iPhone. It allows you to play this fascinating game against random players from all over the world.

The rules are simple - two players take turns choosing to 'cooperate' or 'compete' with each other. If both players cooperate, they both earn points. However, if one player cooperates and the other competes, the competing player will earn a bigger reward and the cooperating player will earn zero. The catch is that if both players compete, then you both earn a very small number of points.

As each turn progresses, the layers get more complex. Do you trust your opponent? Are you worried they will retaliate? Should you retaliate for their actions or be more forgiving?

You can see that beneath the simple exterior lies a complex and intense psychological standoff.

The paradox is that it's in your best interest to compete at every turn. But if you take that strategy, your opponent is likely to take the same strategy and you'll both wind up with extremely low scores.

Remember that this is NOT a zero-sum game - both players can wind up with high scores, or both players can wind up with very low scores.

So the choice is up to you - how much should you cooperate and how much should you compete?

The game can be used as a model for human behavior in a huge variety of areas - economics, business, politics, social psychology, biological sciences, and on. Any situation where you need to balance short-term gain with long-term cooperation contains elements of the Prisoner's Dilemma.

What's New in Version 1.1

Note to players: If you are having difficulty finding a match, log in at 8PM in your local time zone. By coordinating actions in this way, you'll be more likely to find other players.

Version notes:
- Now plays sound when a match is found, making it easier to find players! You can just leave it on a table while it searches for players.
- Shows an alert message if there is any problem finding a match.
- Added sounds for button clicks.
- Removed crash that would happen if you waited for too long before submitting score.


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