Paolo Paruolo|Michaela Saisana|Andrea Saltelli
Ratings and Rankings: Voodoo or Science?
University of Insubria|Joint Research Centre|Joint Research Centre
summary composite indicators aggregate set variables using weights understood reflect variables importance index propose measure importance given variable within existing composite indicators via karl pearsons correlation ratio call measure main effect socioeconomic variables heteroscedastic correlated relative nominal weights hardly ever found match relative main effects propose summarize discrepancy divergence measure discuss extent mapping nominal weights main effects inverted analysis applied six composite indicators including human development index two popular league tables university performance found many cases declared importance single indicators main effect different data correlation structure often prevents developers obtaining stated importance even modifying nominal weights set nonnegative numbers unit sum