Abstract
In this paper, a systematic method to design rating scale is proposed. The rating scale used by respondents in various subjective evaluation ought to be easy to rate for them. This study aims (1) to clarify existence of individual preference towards scale design, i.e., easy / difficult to answer, and (2) to propose a system that treat differences of the preference and individual meaning of categories. To obtain fundamental findings for constructing system, two psychological experiments are executed; the experiments consist of (1) tasks of choosing and assigning rating categories, and (2) ranking of the variously designed scales in terms of easiness of rating and assignment of the rating categories. From the results obtained, existence of individual preference towards various scales is exemplified, first. Next, some factors that affiliate evaluation of easiness of rating are extracted to clarify the factors required to treat in the system. Then, relationship between easiness of rating and assignment of categories is examined through comparison among subjective rankings of easiness of rating scales, subjective rankings of assignment of categories and 14 mathematical indices for evaluating the assignment to compose a strategy for treating these factors. In the next stage, methodology of estimating easiness of rating from those index values will be discussed to show scheme of the system. Lastly, combining methodologies and findings obtained in this study, a system that supports to design a customized rating scale for each respondent through interaction is proposed.
