Twelve classic games
Related games sit side by side, so drag or scroll in any direction. Tap ⇄ to see the one thing that separates two neighbours.
Trust and coordination
Who gives way
Pure conflict
Taking turns
Markets and auctions
Prisoner's dilemma
Stag hunt
Battle of the sexes
Chicken
Hawk-dove
Penalty shootout
Rock paper scissors
Ultimatum game
Centipede game
First-price sealed-bid auction
Cournot duopoly
Hotelling linear city
Trust and coordination
Prisoner's dilemmaIndividually rational choices can make everyone worse off, and talking about it does not help.Stag huntWhen cooperation is not dominated, the obstacle is not greed but doubt about the other.Battle of the sexesAgreeing matters more than what you agree on, but the two of you disagree about which to agree on.Who gives way
ChickenBoth equilibria need someone to give way, so the fight is over who is believed to be unable to.Hawk-doveAggression pays only while it is rare, so a population settles at a mix rather than on a type.Pure conflict
Penalty shootoutWhen your two options differ in strength, equilibrium mixing is not fifty-fifty but is tuned so that the opponent gains nothing by leaning either way.Matching penniesWith pure opposed interests there is nothing to settle on, so the only stable play is to be unpredictable.Rock paper scissorsBest responses can run in a circle, so no choice is safe and the only stable play is to be equally unpredictable across three options rather than two.Taking turns
Ultimatum gameProposing first in a one-shot split lets you keep nearly all of it, and the fact that real responders turn such offers down is the plainest evidence that payoffs are not money.Centipede gameBackward induction can unravel a long and mutually profitable sequence at its very first move, and the longer the sequence the more obviously wrong the prediction looks.Markets and auctions
First-price sealed-bid auctionWhen you pay what you bid you must shade below your value, and the right bid is simply what you expect the strongest rival to be worth in exactly those cases where your bid wins.Cournot duopolyCompeting in quantities leaves each firm producing output that its rival would rather it did not, so the market settles strictly between monopoly and perfect competition instead of at either extreme.Hotelling linear cityThe margin a firm can hold is precisely what it costs its marginal buyer to switch, so differentiation is not a by-product of competition but the thing that makes any profit possible at all.The glossary has every term in plain English.