ORCON - a tool for analysis of ordinal consistency in a pairwise comparison matrix

Decision makers are often asked to make pairwise comparisons in the process of decision analysis with multiple criteria. Experiences show that decision makers make errors in expression of their judgements leading to ordinal and/or cardinal inconsistency in the comparison of objects. If results are highly inconsistent, the revision of a decision maker's comparisons should be carried out. The process may be quite complicated and usually is not part of the method. Ordinal consistency is often the first step to the success in many decision processes. We propose ORCON - an Excel-based tool that provides: 1) record of all cycles in the matrix of pairwise comparisons; 2) a list of all possible changes leading to consistency; 3) way to carry out those changes. The process is illustrated through ORCON application in a multi-criteria selection task.