Metrology of human-based measurements

Abstract

Demands for quality assured measurement are increasing, not only from sectors such as health care, services and safety, where the human factor is obvious, but also from manufacturers of traditional products of all kinds who need to assure the quality of their products as perceived by the customer. The metrology of human-based observations is however in its infancy-concepts such as traceability and uncertainty are poorly developed as yet. This paper reviews how this can be tackled with a measurement system analysis approach, particularly where Man acts as a measurement instrument. Connecting decision risks when handling qualitative observations with information theory, perceptive choice and generalized linear modelling-through the Rasch invariant measure approach-enables a proper treatment of ordinal data and a clear separation of person and item attribute estimates. This leads in turn to opportunities of establishing measurement references for metrological quality assurance. The measurement units associated with the Rasch attribute parameters should be intimately related to metrological traceability and measurement standards. In psychometrics, we could imagine a certified reference for knowledge challenge, for example, a particular concept in understanding physics or for product quality of a certain health care service.