Zero-Sum Betting Game Interview Questions
Zero-sum betting game interview questions covering payoff conservation, each side expected value, information advantage, spread, and fees.
Candidates facing two-player betting or trading-game prompts.
Zero-sum means payoffs offset
In a zero-sum toy game, one player's gain is the other player's loss before any external costs. The total payoff across players is constant.
Compute each side separately
Even when total payoff is zero, each participant can have different expected value if they have different information, prices, or constraints.
Concrete example
If you win 1 when a coin lands heads and lose 1 when it lands tails, your opponent has the opposite payoff. With a fair coin, both sides have zero EV before costs.
Information can create edge
If one side has a better probability estimate, the game can be positive EV for that side at the offered price and negative EV for the other side.
Fees make the total negative
Once spread, commission, or entry fees are included, the combined payoff to participants can become negative even if the pre-cost game is zero-sum.
Common mistakes
Candidates often conclude no one can have edge in a zero-sum setup. Zero-sum describes payoff conservation, not equal information or equal decision quality.
Practice the pattern
Use the LeetQuidity curriculum and calibration to turn this topic into a focused practice plan.