Finally, as already mentioned in section 2.3.2, Cho et al. [18] combine Decision
Trees and Association Rule Mining in a web shop RS. In their system, association rules are derived in order to link related items. The recommendation is then
computed by intersecting association rules with user preferences. They look for association rules in different transaction sets such as purchases, basket placement, and
click-through. They also use a heuristic for weighting rules coming from each of the
transaction sets. Purchase association rules, for instance, are weighted higher than
click-through association rules.