The attitude expressions elicited i

The attitude expressions elicited in sur¨eys can be classified as category scales or
magnitude scales. These terms are borrowed from the field of psychophysics, the
study of the functions that relate quantitative expressions of subjective reactions to
physical variables. For example, the perceived loudness of tones that vary in
amplitude can be measured on a bounded category scale e.g., from ‘not loud at all’
to ‘very very loud’.. Loudness can also be measured on a magnitude scale by
presenting the subject with a series of tones, with the instruction to assign a given
number known as the modulus. to a specified standard tone, and to assign
numbers to other tones relative to this common modulus. The defining characteristics
of a magnitude scale are that it is unbounded, has a meaningful zero, and
expresses the ratios of the relevant underlying variable.