Incremental Mining Algorithm of Sequential Patterns Based on Sequence Tree

At present, the existing incremental mining algorithms of sequential patterns can not make full use of the mining information in original database, the updated database is scanned many times and the projected databases for frequent items are constructed. In this paper, we propose an incremental mining algorithm of sequential patterns based on Sequence tree, called ISPBS. ISPBS uses the sequence tree (Stree) to store the mining information in the original database. Sequence tree is a novel data structure, it is similar in structure to the prefix tree. But the sequence tree stores all the sequences in the original database. When the database is updated, ISPBS only deals with the incremental sequences and adds the sequences to the sequence tree without constructing the projected database. It can find all the sequential patterns in the updated database by scanning the sequence tree. Experiments show that ISPBS outperforms Prefix Span and Inc Span in time cost.