Stock Market
Buyers value an asset and sellers have reservation costs. Bid–ask matching mimics a simplified exchange.
Market
Clearing price—
Trades0
Consumer surplus0
Producer surplus0
Social welfare0
Buyers
Sellers
How this teaches game theory
A double auction is a two-sided market: buyers strategically submit bids while sellers strategically submit asks. Trades occur when compatible offers overlap. The simulator highlights market clearing, gains from trade, surplus, and the effect of strategic shading.
Complete scenario, mode, and level guide
Energy Market
Buyers represent demand and sellers represent generators with different marginal costs.
Online Marketplace
Buyers and sellers bargain through platform-submitted offers for a standardized item.
Modes
Human Buyer vs Bots
You control one bid. Your utility depends on buying below your private value.
Human Seller vs Bots
You control one ask. Your utility depends on selling above your private cost.
Human Controls Market
Your slider shifts the most aggressive order on both sides so you can observe how the market-clearing point moves.
Computer Market
All offers are generated automatically and the simulator demonstrates clearing without human intervention.
Levels
Level 1 — 3 × 3
A small market makes each bid, ask, and trade easy to follow.
Level 2 — 5 × 5
More participants create deeper competition and a more stable market-clearing price.
Level 3 — Dynamic Arrivals
New agents appear between rounds, illustrating how market conditions can change over time.
Key idea: efficient trade occurs when buyer value exceeds seller cost. Strategic bids and asks affect who trades and how the gains from trade are divided.