On the Concept of Measuring System in Measurements Based on Jury Testing Methods

摘要

The interaction of persons with their living and working environment is a key point for the quality of life and for growth.The most direct feedback for improving this kind of interaction -- including all kinds of devices used - isprovided by "measuring" relevant parameters that are directly related to the various aspects of human perceptionand adaptation to them. Many of these measurements combine "hard" measurements with the psychological or some other element that is difficult to measure objectively and are often referred to as "soft" metrology [1-7].Such measurements are very challenging as well as inherently appealing, since they are customer oriented,highly informative and provide direct information on the perceived quality of the quantity to be measured. On the other hand, users' confidence in them can be less than in common physical or engineering quantities.This lack of confidence is in part due to the inherent interand intra- individual variability related to phenomenainvolving perception and its dependence on contextual factors, but even more to the lack of standardisation of themethods and to the absence of internationally recognized metrological references.A key technique for such measurement is jury testing, which is the method necessary for directly assessing the humanperceptive response to some kind of stimuli. At present the metrological status of such techniques is far from beingdefined, in spite of their relatively significant diffusion. One key point in this problem may be identified in the nature of the measuring system involved (actually the concept of measurement system seems to have come recently to more attention in measurement theory tout court). So, two questions arise f is it possible to identify a measuring system as associated to this kind of measurement? And if so which are its essential features?In this paper we propose a discussion of these points. In doing so, we will considered an illustrative exampleincluding some results concerning the measurement of the quality of sound (pleasantness) of post sorting machines,performed in our laboratory.