Trading Station

quote it, carry it, and answer the follow-up before the clock runs out

no sessions yet

Market making

The city product is the reported IMC exercise: distance times the population of one city times the population density of the other. You give your three inputs first, so the app can check your quote against your own arithmetic.

Fermi sprint

Price a contract

The convention is always the same and is printed on every question: the mid of the market you are shown is the fair value, and its width is one standard deviation.

Data

0:00

Debrief

Every question, in order

What was asked, what you answered, what the right answer was, and why. Read this before the marks.

Where the marks went

Your quotes and trades

0:00

Shorthand works: 4.5bn, 83m, 1.2e9, 272.

Fermi debrief

Question by question

0:00

Contracts debrief

Question by question

The method you are marked against. Count how far the strike is from your fair, in sd, then ask: does it pay if it settles at my fair?

distance0½ sd1 sd1½ sd2 sd
out of the money50%31%16%7%2%
in the money50%69%84%93%98%

Digital: the chance it pays. Call or put, out of the money: the chance × about two thirds of an sd (at the fair, 0.4 sd). In the money: intrinsic + the out-of-the-money price at the same distance. Put from a call: call − (fair − strike). After a move: shift the fair and read the table again.

Progress

Brief

The quote ritual

  1. Clarify. Restate the quantity and ask the one question that resolves the planted ambiguity. On a city market that is always the boundary definition.
  2. Decompose out loud. Two to four assumptions, each a number someone could check.
  3. Quote. "My market is X at Y." Fair inside, and say why that width.
  4. Move with the flow. Every trade against you shifts both prices and tells you something.
  5. Know your position and your P&L at every instant, because they will ask mid-calculation.

Width is a derived number, not a habit

For a product, relative errors add in quadrature. Three percent on a distance, ten on a population and fifteen on a density give sqrt(0.03² + 0.10² + 0.15²) = 18%. Quote about one standard deviation wide in total and say that sentence out loud. A spread you can decompose beats a spread you cannot.

The identities that must hold across your own quotes

What else they might put in front of you

Ranked by how often the reported corpus sees them at this stage.

  1. Fermi market making. The core. An invented quantity, a two-way price, then trades.
  2. Compound and derived markets. This year's version: a triple product, then the ratio, the area, a component. Graded on consistency as much as accuracy.
  3. Higher-lower with Kelly sizing. Thirteen cards, a bankroll, stake 2p - 1. Pass at the seven, bet everything on a certainty.
  4. The card-sum market. Quote a market on the sum of the next three cards, with a running count as the deck depletes. Fair for a fresh deck is 21 with ace low.
  5. Dice markets. Sum of three dice, the higher of two, an option to reroll. Price the reroll as value-with minus value-without.
  6. A prior against a market. You are told a probability and shown a price on a hundred-contract. Trade only where your fair is outside their quote, and say why your information is not already in the price.
  7. Odds, the overround, and dutch books. Decimal d implies 1/d. American +X implies 100/(X+100). If the implied probabilities sum below one, stake in proportion to 1/d and lock the difference.
  8. Event quoting. A tennis match, an election, a sporting result. Same ritual, softer anchors.
  9. Order-book mechanics. Where you get filled, the mid, the volume-weighted price of taking size, what your resting order does. This is the prerequisite for any simulator station.
  10. Options basics. Name the five Greeks, the short-put payoff, put-call parity and the conversion trade. Basics only, by their own account.
  11. Common-value auctions. A jar of coins, sealed bids. Winner's curse: shade more as bidders multiply. Second-price makes truthful bidding dominant.
  12. Pricing a game. "How much would you pay to play?" Expected value, then the option value of being allowed to stop, then a risk haircut.
  13. Group exercises. Some accounts report a shared trading game. Collaboration is explicitly weighted at this stage.

The five rules that decide the round