Modeling interactive behaviour of a video based multimedia system

We report on the statistics of user behaviour obtained during a semester of student usage of our video-on-demand based multimedia system. The statistics show that interactive behaviour is adequately modelled by exponential distributions, but that a better match is obtained from lognormal distributions. From the statistics we develop a model of interactive behaviour that consists of a Markov chain of video interactions overlaid by a Poisson process generating other interactions. We show that the model performs quite well, and provided caution is exercised, Markov processes are adequate models of interactive behaviour.