Associative Measurement of Psychological Magnitude
Lawrence M. Ward University of British Columbia
With the arrival of your most precious wine, and with this heat, my meditation is about measuring the aforesaid heat and cooling the wine.
--Letter from Sagredo to Galileo ( July 27, 1613, quoted by Middleton, 1966, p. 7)
Attempts to measure psychological magnitudes have a long history. In fact, as the preceding quote intimates, psychological magnitudes provided the impetus for much, if not all, of physical measurement, which has now reached a state of precision and depth that mocks the continuing efforts of psychophysicists to grasp the gold ring from the merry-go-round of psychophysical scaling. In this chapter I summarize some salient aspects of our struggle and then make two proposals that represent departures from current practice in the direction of what I see as the establishment of a useful procedure to measure psychological magnitude. I propose that we attempt to measure a "universal" psychological magnitude associatively, as temperature is measured. However, before getting to the proposals, some foundational issues deserve comment.
It is common (although often tacit) knowledge that science and measurement are mutually interdependent. Among the numerous examples are the