Ascending frequency ordered prefix-tree: efficient mining of frequent patterns

Mining frequent patterns is a fundamental and important problem in many data mining applications. Many of the algorithms adopt the pattern growth approach, which is shown to be superior to the candidate generate-and-test approach significantly. We identify the key factors that influence the performance of the pattern growth approach, and optimize them to further improve the performance. Our algorithm uses a simple while compact data structure-ascending frequency ordered prefixtree (AFOPT) to organize the conditional databases, in which we use arrays to store single branches to further save space. We traverse our prefix-tree structure using a top-down strategy. Our experiment results show that the combination of the top-down traversal strategy and the ascending frequency item ordering method achieves significant performance improvement over previous works.