Dotted suffix trees - A structure for approximate text indexing

In this work, the problem we address is text indexing for approximate matching. Given a text, T which undergoes some preprocessing to generate an index, we can later query this index to identify the places where a string occurs up to a certain number of errors k (edition distance). The indexing structure occupies space O(n log(k) n) in the average case, independent of alphabet size. This structure can be used to report the existence of a match with k errors in O(3(k) Mk+l) and to report the occurrences in O(3(k) m(k+l) + ed) time, where m is the length of the pattern and ed and the number of matching edit scripts. The construction of the structure has time bound by O(kN\Sigma\), where N is the number of nodes in the index and \Sigma\ the alphabet size.