Application of Markov chains to quality evaluation of information entering by a computer system user

Problems of human-computer interaction modelling are considered in this paper. The aim was the quality evaluation of the user activity. The need of performing such evaluations occurs in the case of computer systems design, destined for control of complex processes, as well as devices being commonly in use. The simplest models are designed to calculate basic characteristics of the user activity, i.e. the command entering time and the command correct execution probability. The theory of Markov chains with rewards is the basis for constructing these models. The use of the elaborated model is shown on an example of simple command entering