Five-Card Market
Five cards are dealt face down from a standard deck (Ace = 1 through King = 13). You make a market on their total. Before each round after the first, one card is revealed. Because cards are not replaced, every reveal also changes the composition of the rest of the deck.
Scoring rules
Each round you enter a fair value, a bid and an ask (ask − bid ≤ 4). Then the round's counterparties arrive in a fixed, seeded order:
- 12 noise traders, each with a random edge between 0 and 4. A noise buyer lifts your ask if ask ≤ public EV + edge; a noise seller hits your bid if bid ≥ public EV − edge. Size 1.
- One informed trader who knows the true value: buys 2 at your ask if ask < true value, or sells at your bid if bid > true value.
- Fills that would take |position| above 12 are rejected.
After the last round the position settles at the true value.
Score = PnL − 0.15 × Σ|position after each round| − 0.5 × Σ|fair value − public EV|
PnL = spread edge (earned versus the public EV) + information PnL (position × (true − EV) at each fill). Target score ≥ 2. The same seed and the same quotes always produce the same result; the final score is recomputed on the server.
Position
0
Cash
0
Mark @ EV
0
Max width
4