ABSTRACT
In descriptive valuing the evaluator chooses the values of others as criteria and standards. The posture is not that these values are paramount, but that they are perceptions of intervention worth that are grist for the mill of decision–making. In prescriptive valuing. the evaluator herself advocates the primacy of particular values, such as, for instance justice, equality and client needs, regardless of whether these values are adopted by any decision–making body or held by some stakeholding constituency. The value component of public sector evaluation was long neglected because the answer appeared obvious: the evaluator should avoid setting up criteria of her own; the natural criteria of merit to apply are the initial, stated intervention goals. All the effectiveness criteria displayed, be they descriptive or prescriptive, have one thing in common: they pay no heed to costs. To remedy this omission, economists have devised cost criteria. The most pertinent cost measurements are productivity and efficiency.
