Mining Closed Repetitive Gapped Sequential Patterns Based on Repetition Linked WAP-Tree
Closed repetitive gapped sequential pattern mining has been gained more and more attention in recent years, in this paper, we propose a novel method MRCGP(mining closed repetitive gapped sequential pattern based on repetition linked WAP-Tree). In the first step of MRCGP, the given sequential database is transformed into a new database in which every item is expressed by its landmark; then a positional information table(PIT) which includes all of the position information of 1-frequent items is constructed, all of the repetitive gapped 2-sequential patterns of different items (RPDI) can be obtained through searching the positional information table; following, a repetitive linked web access pattern tree (RLWAP-Tree) is built, in RLWAP-Tree, the 1-frequent items are stored as header table, the items in header table will be linked to their same items which appear earliest in each sequence corresponding to RLWAP-Tree with solid line, all of the items in RLWAP-Tree are linked to their same items in the same sequences with broken line; through mining projection tree of the existing repetitive gapped pattern recursively, we can obtain the repetitive gapped sequential pattern; at the end, we get the closed repetitive gapped sequential pattern by checking inclusion relation of any two patterns. The experiment result shows MRCGP has better time efficiency.