Abstract: One-off sequential pattern mining aims to mining repetitive sequential patterns with gap constraints from sequence. However, current methods do not consider the users’ degree of interest, and treat each character in the sequence equally, which leads to mining many redundant patterns that are uninteresting to users. In order to solve this problem, proposed the one-off three-way sequential pattern (OTP) mining problem by introducing the concept of three-way decision and its efficient solution algorithm OTPM. In terms of support calculation, OTPM algorithm is based on the depth-first search and backtracking strategy, and combines the characteristics of three-way patterns to efficiently solve the support of patterns. In the generation of candidate patterns, OTPM algorithm uses a pattern join strategy to reduce the number of candidate patterns. In addition, a parallelization scheme also is used in OTPM algorithm, improve the mining efficiency of the algorithm by taking full advantage of the multi-core performance of modern processors. Finally, the experimental results verify the significance of studying the OTP mining problem and the efficiency of the OTPM algorithm.

Key words: sequential pattern mining, three-way decision, three-way sequential pattern, one-off, parallel algorithm