Market Making Coin Game Interview Questions
Market making coin game interview questions for quoting binary coin outcomes, streak events, and biased-coin markets.
Candidates practicing coin-based trading games.
Define the coin event
The market could be on the next flip, a streak, the number of heads, or a stopping event. Define the payoff event before quoting.
Fair coin does not always mean price 50
A next-flip heads contract on a fair coin has fair value 50 on a 0-to-100 scale, but streak and path-dependent events need separate probabilities.
Concrete example
A contract paying 100 if two fair flips are both heads has fair value 25 before spread because the probability is 1/4.
Handle biased coins explicitly
If the coin is biased, state the probability and update the fair value from that probability rather than assuming 50 percent.
Quote with uncertainty
If the bias is estimated rather than known, widen the spread or reduce size to reflect uncertainty.
Common mistakes
Candidates often say coin and immediately use 50 percent. The event and bias assumptions matter.
Practice the pattern
Use the LeetQuidity curriculum and calibration to turn this topic into a focused practice plan.