A Method of Variable Ordering for Zero-suppressed Binary Decision Diagrams in Data Mining Applications Authors: Haruya Iwasaki, Shin-ichi Minato, and Thomas Zeugmann Source: Proceedings of The Third IEEE International Workshop on Databases for Next-Generation Researchers, SWOD 2007, pp. 85 - 90, IEEE 2007. Abstract. Recently, an efficient method of database analysis using Zero-suppressed Binary Decision Diagrams (ZBDDs) has been proposed. BDDs are a graph-based representation of Boolean functions, now widely used in system design and verification. Here we focus on ZBDDs, a special type of BDDs, which are suitable for handling large-scale combinatorial itemsets in transaction databases. The ZBDD size greatly depends on the variable ordering used. In this paper, we propose a new method of ZBDD variable ordering for itemset mining of large-scale transaction databases, and show experimental results. ©Copyright 2007, IEEE