# Stochastic Models

Stochastic models provide a framework for either
probabilistic verification or statistical validation.
Probabilistic verificaiton may assert, for example,
that with high probability, a design will stay
within operating parameters for all possible inputs.
Statistical validation may assert, for example,
that a large percentage of usage scenarios will
result in performance that is satisfactory to the user.
Stochastic models are particularly useful for
assessing **reliability** of a system, providing
either probabilities of failure or statistical assertions
about failure.