Let $ \Theta $ be a finite alphabet. We consider a bundle of measure preserving transformations $ (T_{\theta})_{\theta \in \Theta} $ acting on a probability space $ (X,\mu) $, which are chosen randomly according to an ergodic stochastic process $ (\Xi,\nu,\sigma) $ with state space $ \Theta $. This describes a paradigmatic case of a random dynamical system (RDS). Considering a finite partition $ \mathcal{P} $ of $ X $ we show that the conditional algorithmic complexity of a random orbit $ x, T_{\alpha_{0}}(x),T_{\alpha_{1}}\circ T_{\alpha_{0}}(x),... $ in $ X $ along a sequence $ \alpha = \alpha_{0}\alpha_{1}\alpha_{2}... $ in $ \Xi $ equals almost surely the fiber entropy of the RDS with respect to $ \mathcal{P} $, whenever the latter is ergodic. This extends a classical result of A. A. Brudno connecting algorithmic complexity and entropy in deterministic dynamical systems.
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