Hitting Probability Quant Interview Guide
Hitting probability quant interview guide for target states, boundary conditions, recursion, random walk examples, and common mistakes.
Candidates practicing random walk and Markov process boundary questions.
Hitting probability asks whether a state is reached
A hitting probability is the chance that a process reaches a target state or boundary, often before reaching a different failure state.
Boundary conditions anchor recursion
Set the probability to one at the target and zero at failure states when appropriate. Then write recursive equations for intermediate states.
Concrete example
For a bounded random walk, the probability of hitting the upper boundary before the lower boundary can be solved from step probabilities and starting state.
State space matters
Discrete and continuous processes use different tools, but the setup is the same: define state, target, failure boundary, and transition behavior.
Common mistakes
Candidates often skip target and failure definitions. The fastest reliable setup is to write the boundary probabilities before any algebra.
Practice the pattern
Use the LeetQuidity curriculum and calibration to turn this topic into a focused practice plan.