1. A computer implemented method of analyzing and graphically representing a correlation of a plurality of transaction items, the method comprising the steps of: retrieving data associated with the transaction items; correlating the transaction items in a dimensionally reduced manner using the retrieved data, graphically representing the correlated transaction items, the graphical representation of the correlated transaction items and the correlated transaction items being linked; creating a tree hierarchy using the retrieved data, wherein the tree hierarchy classifies the transaction items in a hierarchy according to a defined user understandable factor; graphically representing the tree hierarchy i) as a graphical overlay over a top of the graphical representation of the correlated transaction items, and ii) as a graphical textual tree hierarchy, the graphical representation of correlated transaction items, the graphical overlay and the graphical textual tree hierarchy all being displayed in a combined graphical representation, wherein the graphical overlay and the graphical textual tree hierarchy are linked to the correlated transaction items and graphically representing in the combined graphical representation an interaction between the correlated transaction items and at least one transaction item in the tree hierarchy by i) detecting a selection in one of the graphical overlay, graphical textual tree hierarchy and the graphical representation of the correlated transaction items and ii) graphically representing how the graphical overlay, graphical textual tree hierarchy and the graphical representation of the correlated transaction items are linked, wherein a selection of a transaction item in the graphical representation of the correlated transaction items results in a visual identification of a corresponding transaction item in the graphical textual tree hierarchy and in the graphical overlay, wherein a selection of a transaction item in the graphical textual tree hierarchy results in a visual identification of a corresponding transaction item in one of the graphical representation of the correlated transaction items and in a corresponding section of the graphical overlay, and wherein a selection in the graphical overlay results in a visual identification of one or more corresponding transaction items in the graphical textual tree hierarchy and in the graphical representation of the correlated transaction items.