Cooperation Simulator
Run strategies against each other in the repeated prisoner's dilemma and watch which behaviours survive.
Requires KIT Apps · Runs locally · 25 KBKIT Apps is free
What you can explore
- Put eight classic strategies in a round-robin tournament and read the score table.
- Change how many rounds each pair plays, and watch short games favour defection.
- Add noise, so moves are occasionally misread, and see which strategies recover.
- Run evolution: let the population reproduce in proportion to score, generation by generation.
How it works
Every pair of strategies plays a fixed number of rounds of the prisoner's dilemma, scoring 3 each for mutual cooperation, 1 each for mutual defection, and 5/0 when one defects against a cooperator. That payoff ordering is the whole problem: defection is the better individual move in any single round, yet a population of defectors scores worse than a population of cooperators. Repetition changes the calculation, because today's move affects tomorrow's treatment. The evolution mode reproduces each strategy in proportion to its total score, which turns the tournament into a crude model of selection.