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Ultimatum Game

A classic experiment in behavioral economics that challenges traditional assumptions about rationality. The proposer offers a split of money, and the responder can accept or reject. If rejected, both get nothing.

Total Pot
$100
You: $50
Them: $50
Drag to adjust your offer
0
Games Played
0%
Acceptance Rate
$0
Average Offer
0
50/50 Splits

About the Ultimatum Game

The Setup: Player 1 (Proposer) is given $100 and must propose a split with Player 2 (Responder). Player 2 can accept or reject the offer.

Rational Prediction: Game theory predicts the proposer should offer $1 and keep $99, and the responder should accept (since $1 > $0).

Actual Results: In experiments, offers below 30% are often rejected! People prefer fairness over money, demonstrating "altruistic punishment."

Key Findings:

• Modal offer: 50/50 (fairness norm)

• Offers below 20% rejected ~50% of the time

• Culture affects results (more collectivist = more fair offers)

• Shows humans value fairness, reciprocity, and punishing unfairness