Quant interview prep guides

Zero EV Fair Game Interview Questions

Zero EV fair game interview questions covering break-even prices, balanced payoffs, and why fair is not always attractive.

Candidates reviewing zero-EV games, entry fees, and payoff balance.

Fair means zero expected value

A fair game has expected net payoff equal to zero under the stated probability and payoff model.

Set EV to zero

To find a fair entry fee or fair payoff, write the expected net value equation and solve for the missing variable when EV equals zero.

Concrete example

A game that wins 1 on heads and loses 1 on tails with a fair coin has expected value 0.5 x 1 + 0.5 x -1 = 0.

Fair is not the same as desirable

A zero-EV game may still be unattractive once utility, risk, opportunity cost, or bankroll constraints matter.

Use fairness as a benchmark

After finding the fair price, compare the offered price with that benchmark to determine whether the proposed game has positive or negative expected value.

Common mistakes

Candidates often say a game is fair because probabilities are equal. Fairness depends on both probabilities and net payoff sizes.

Practice the pattern

Use the LeetQuidity curriculum and calibration to turn this topic into a focused practice plan.