What is a stochastic system?

Tim Chung, 07 Oct 02

The word "stochastic" means "pertaining to chance" (Greek roots), and is thus used to describe subjects that contain some element of random or stochastic behavior. For a system to be stochastic, one or more parts of the system has randomness associated with it. Unlike a deterministic system, for example, a stochastic system does not always produce the same output for a given input. A few components of systems that can be stochastic in nature include stochastic inputs, random time-delays, noisy (modelled as random) disturbances, and even stochastic dynamic processes.