Optimal Stopping Interview Questions
Optimal stopping interview prep for stop-versus-continue values, backward induction, offer problems, and horizon mistakes.
Candidates practicing stopping rules and expected value decisions.
Stop versus continue
Optimal stopping compares the value of stopping now with the expected value of continuing under the rules.
Backward induction
For finite-horizon problems, start at the last decision point and work backward. The final step often makes the rule clear.
Concrete example
If you can keep a current offer of 6 or redraw once from a die, the continue value is 3.5, so stopping is better in the simple EV model.
Threshold rules
Many stopping problems create thresholds: stop when the current value exceeds the continuation value.
Horizon matters
A rule with one remaining attempt may differ from a rule with many attempts. Always state the time horizon.
Common mistakes
Candidates often compare current value with the unconditional average instead of the correct continuation value.
Practice the pattern
Use the LeetQuidity curriculum and calibration to turn this topic into a focused practice plan.