ABSTRACT
Studying people’s beliefs, attitudes, values, and personalities is a central research preoccupation of the social sciences. This focus on differences among individuals requires that data be organized and conceptualized in a systematic and precise manner, a manner different from that used in stimulus scaling, which we discussed in chapter 14. Whereas we assume in the methods of pair comparison and rank order scaling that all participants would respond identically to the various choice stimuli were it not for random error, the scaling of individual differences requires that we regard variations in responses among participants as meaningful (i.e., as not attributable to error). Conversely, the stimuli used to assess individual differences (typically the questions or “items”in the scale or questionnaire) are assumed to be identical in meaning for all participants, and to be measuring essentially the same idea, knowledge base, or attitude. Differences in participants’responses to these hypothetically “identical”items are the central methodological focus in the scaling of individuals.
