ABSTRACT
The motivation for considering what seems to be a general problem in a very circumscribed way, as is to be done here, arises from results reported by Gregson (1986) on the problem of hypoadditivity in olfactory psychophysics. Hypoadditivity is a phenomenon in which the intensity of a total mixture is in some sense less than the sum of the component intensities experienced separately. Some background is helpful, as is the use of a notation appropriate to draw distinctions between responses to a single stimulus in isolation, and to the same stimulus when it is a component of a mixture, or is partly masked by system noise which is permanently present.
