Recurrence Plots for Symbolic Sequences

This paper introduces an extension of recurrence analysis to symbolic sequences. Heuristic arguments based on Shannon-McMillan-Breiman theorem suggest several relations between the statistical features of ‘symbolic’ recurrence plots and the entropy per unit time of the dynamics; their practical efficiency for experimental sequences of finite length is checked numerically on two paradigmatic models, namely discretized logistic map trajectories and Markov chains, and also on experimental behavioral sequences. Specific advantages of RP analysis are presented, among which the detection of non stationary features. Abbreviations – RP: recurrence plot; m-RP: plot describing the recurrence of m-words; RPm(w): partial RP describing the recurrence of the m-word w.