Merit is the absolute or relative quality of something, either overall or in regard to a particular criterion (see Criteria). To determine the merit of an evaluand in regard to a particular criterion, it is necessary to collect relevant performance data and to explicitly ascribe value to it; that is, to say how meritorious the evaluand is in that particular dimension. To determine the overall merit of the evaluand, a further step is required: synthesis of performances with multiple criteria (see Synthesis). Merit determination and synthesis are two of the core methodological tasks that distinguish evaluation from the collection and reporting of descriptive data for interpretation by others.