A hybrid framework for mining high-utility itemsets in a sparse transaction database

摘要

High-utility itemset mining aims to find the set of items with utility no less than a user-defined threshold in a transaction database. High-utility itemset mining is an emerging research area in the field of data mining and has important applications in inventory management, query recommendation, systems operation research, bio-medical analysis, etc. Currently, known algorithms for this problem can be classified as either 1-phase or 2-phase algorithms. The 2-phase algorithms typically consist of tree-based algorithms which generate candidate high-utility itemsets and verify them later. A tree data structure generates candidate high-utility itemsets quickly by storing some upper bound utility estimate at each node. The 1-phase algorithms typically consist of inverted-list based and transaction projection based algorithms which avoid the generation of candidate high-utility itemsets. The inverted list and transaction projection allows computation of exact utility estimates. We propose a novel hybrid framework that combines a tree-based and an inverted-list based algorithm to efficiently mine high-utility itemsets. Algorithms based on the framework can harness benefits of both types of algorithms. We report experiment results on real and synthetic datasets to demonstrate the effectiveness of our framework.