stochastic music
stochastic music (from Gk. stokhos, ‘aim’).
Originally a mathematical term, a ‘stochastic process’ being one whose goal can be described but whose individual details are unpredictable. In music, it refers to composition by the use of the laws of probability. By contrast with *indeterminate music, stochastic music is fully composed: chance enters only into the process of composition, the composer perhaps allowing the distribution of pitches, for example, to be determined by some concept from the mathematics of probability. Stochastic techniques, which often depend on the use of a computer to calculate distributions, can be useful in the creation of sound masses where the details are less important than the large-scale effect. The word was introduced into the musical vocabulary by Xenakis, much of whose music is stochastic.
