Group decision systems for ranking and selection an application to the accreditation of doping control laboratories

This paper presents a qualitative approach for representing and synthesising evaluations given by a team of experts involved in selection or ranking processes. The paper aims at contributing to decision-making analysis in the context of group decision making. A methodology is given for selecting and ranking several alternatives in an accreditation process. Patterns or alternatives are evaluated by each expert in an ordinal scale. Qualitative orders of magnitude SPAces are the frame in which these ordinal scales are represented. A representation for the different patterns by means of k-dimensional qualitative orders of magnitude labels is proposed, each of these standing for the conjunction of k labels corresponding to the evaluations considered. A method is given for ranking patterns based on comparing distances against a reference k-dimensional label. The proposed method is applied in a real case in External Quality Assessment Schemes (EQAS) for Doping Control Laboratory contexts.