In the market basket setting, we are given a series of transactions each
composed of one or more items and the goal is to find relationships
between items, usually sets of items that tend to occur in the same
transaction. Association rules, a popular approach for mining such data,
are limited in the ability to express complex interactions between
items. Our work defines some of these limitations and addresses them by
modeling the set of transactions as a network. We develop both a general
methodology for analyzing networks of products, and a privacy-preserving
protocol such that product network information can be securely shared
among stores. In general, our network based view of transactional data
is able to infer relationships that are more expressive and expansive
than those produced by a typical association rules analysis