Return intervals in a text.

<p>(a) shows the word sequence of Les Miserables from word 31096 to word 31116. Punctuations are considered as words. The sequences beneath illustrate how the return intervals between rare words and their lengths are defined: For <i>R</i>_<i>Q</i> = 2 and 4, only words with ranks above the corresponding <i>Q</i> value (here: <i>Q</i> = 46 and 544, respectively) are picked out and denoted by the large bars. The other words are denoted by the small bars. The return intervals are the intervals between consecutive large bars, i.e. the number of small bars between 2 consecutive large bars plus 1, and are listed beneath the sequences. (b) shows, in a segment of 300 words, the position of words with ranks above <i>Q</i> = 544, 2731, and 7265. The corresponding mean return times are <i>R</i>_<i>Q</i> = 4, 8, and 16, respectively. For <i>R</i>_<i>Q</i> = 8 and 16, the words are not distributed homogeneously but tend to cluster.