Rules & how it works

A price is just a probability.

Each share costs between 1¢ and 99¢, and the price is simply the room’s estimate of the odds — 63¢ means the room thinks it’s about a 63% chance.

A correct share earns you $1.

Each market is a question; you buy shares in the answer you expect. When it’s decided, every share on the answer that actually happened cashes out for $1.00, and the rest are worth $0.00. So if you pay 40¢ for a share you believe is really 60% likely, you come out ahead when you’re right — buy below your honest estimate, sell above it.

Whole shares, penny prices.

You trade whole shares — one share earns you $1 if it wins. Prices move in 1¢ steps; no fractions.

How a trade happens.

Every market has an automated market maker, funded by the organizers, that quotes a buy and a sell price at all times — you never wait for another forecaster to show up. Take its price and your trade fills instantly; every buy nudges the price up and every sell nudges it down, which is exactly how your information becomes the forecast. Prefer patience? Name your own price with a limit order and it rests on the book until the maker's curve — or another forecaster — meets it. Trading is free — no fees. (Curious how the maker sets its prices? See the market maker, explained.)

Trading stops before the event.

Each market locks before its event begins, so this stays about forecasting rather than frantic live-betting. A match closes at kickoff — not during the game — and the daily stock-index markets close before the next trading day, settling on the previous day’s closing price.

One equation quotes every price.

The maker runs Hanson's Logarithmic Market Scoring Rule (LMSR), the classic automated-market-maker design from the prediction-market literature. It keeps a tally q_i of the net shares it has sold of each outcome, and prices everything off a single cost function:

The price is a softmax.

The marginal price of outcome i is the gradient of C: p_i = e^qᵢ/b / Σ_j e^qⱼ/b. Yes — the price you're trading is literally a softmax over the maker's inventory, with temperature b. That guarantees the quotes always form a coherent probability distribution: every price sits between 0 and 1, and across a market's outcomes they sum to 100%.

b is the liquidity dial.

The parameter b sets market depth — how many shares it takes to move the price one cent. Higher b means a calmer market where small trades barely register; lower b means each trade speaks louder. The organizers pick b when they seed a market, trading off stability against responsiveness.

The seed is a bounded subsidy.

Whatever happens, the maker's worst-case loss is capped at b · ln(n) for n outcomes — a fixed stake the organizers put up when they seed a market. That stake is not a fee on you; it's the price the organizers pay the room for its collective forecast, and it flows to whoever traded the price toward the truth.

Why honesty is the best strategy.

If the price is below your honest probability, buying has positive expected value — and it stays positive until the price reaches your estimate. So the profit-maximizing move is to push the price to what you actually believe, then stop. LMSR is a proper scoring rule in market form: it pays you exactly for the information you add.

Still an order book underneath.

In practice the maker discretizes its curve into a ladder of small resting orders and atomically re-posts them after every trade. That's why limit orders work here too: name your price, and either the maker's next quote or another forecaster can meet it.

Ranked by total value

Your standing is your cash plus the mark-to-market value of your open positions — every share valued at its current market price. Good forecasts compound; bad ones show up fast.

Top 3 take the podium.

The top 3 forecasters win real prizes from the organizers. Each tier is a top-tier AI subscription (your choice of Claude or ChatGPT):

• 1st place~$300 valueOne month of Claude/ChatGPT Max (20×), plus a second month at Max (5×)
• 2nd place~$200 valueOne month of Claude/ChatGPT Max (20×)
• 3rd place~$100 valueOne month of Claude/ChatGPT Max (5×)

Prizes are subject to terms and conditions, including but not limited to a minimum number of participants and a minimum number of trades, as determined by the workshop organizers.

The clock that counts.

Rankings lock to portfolio value at Jul 11, 2026, 5:00 PM KST (5:00 PM KST, July 11, 2026). Trade right up to the bell.

Best Paper — resolves 4:00 PM KST.

The Best Paper market is resolved by the organizers when the award is announced at Jul 11, 2026, 4:00 PM KST (4:00 PM KST). Winning shares pay $1.00, the rest expire worthless.

World Cup — resolved automatically.

World Cup markets settle automatically from the official sports results as matches conclude. No human in the loop, no debate — the scoreboard decides.