A computer implemented method of analyzing and graphically representing the correlation of a plurality of transaction items, the method comprising the steps of: retrieving data associated with groups of the transaction items, correlating a plurality of groups of transaction items in a dimensionally reduced manner, creating a tree hierarchy which classifies the groups of transaction items in a hierarchy according to a defined user understandable factor, wherein the tree hierarchy is linked to the groups of transaction items, and graphically representing the correlated groups of transaction items and tree hierarchy to enable interaction between the correlated groups of transaction items and the linked tree hierarchy.