entropy of a transformation given a partition

entropy of a transformation given a partition

[′en·trə·pē əv ə tranz·fər′mā·shən ′giv·ən ə pär′tish·ən]
(mathematics)
If T is a measure preserving transformation on a probability space and ξ is a finite partition of the space, the entropy of T given ξ is the limit as n → ∞ of 1/ n times the entropy of the partition which is the common refinement of ξ, T -1ξ, …, T -n +1ξ.