This chapter considers a probabilistic reasoning based investigation of an information system concerned with consumer choice. The DS/AHP technique for multi-criteria decision making is employed in this consumer analysis, and with its development formed from the Dempster-Shafer theory of evidence and the well known Analytical Hierarchy Process, it is closely associated with the notion of soft computing (in particular probabilistic reasoning). Emphasis in the chapter is on the elucidation of a marketing information system (expert system), which includes results on; the levels of judgements made by consumers, the combination of their preference judgements and results in the formulation and size of consideration sets of cars (within the considered car choice problem). Tutorial, graphical and tableau results are presented to enable the reader, unfamiliar with this form of soft computing, the clearest opportunity to follow its novel form of analysis and information content.