StochasticStochastic means random.
In music, or other fields, the term "stochastic" refers to randomly generated, statistical, elements. In probability theory stochastic processes are studied, in which a system such as a queue evolves over time subject to random factors.
Stochastic processes can be used either to compose a fixed piece, or produced in performance. Such music is also known as aleatoric music. This process was pioneered by Iannis Xenakis, and John Cage, notably with Music of Changes.
In artificial intelligence the term "stochastic" specifically refers to an environment that is non-deterministic in that the next state of the environment is not fully determined by either the previous state of the environment or the actions of the agent. A deterministic environment is much simpler for an agent to deal with.
- Formalized Music: Thought and Mathematics in Composition by Iannis Xenakis, ISBN 1576470792