The problem of mining association rules over basket data was introduced in [AIS93b]. An
example of such a rule might be that 98% of customers that purchase tires and auto accessories also
get automotive services done. Finding all such rules is valuable for cross-marketing and attached
mailing applications. Other applications include catalog design, add-on sales, store layout, and
customer segmentation based on buying patterns. The databases involved in these applications are
very large. It is imperative, therefore, to have fast algorithms for this task.