Chapter 3 Abstract

 

This chapter and the next tell the story about designing the item: the ways that the measurer uses to stimulate the respondent to produce products and behaviors that can be used as the basis for observations about the location of the respondents on the construct in question. By “observation,” something more is meant than just seeing something and recording it, or remembering it, or jotting down notes about it. In referring to it as a special sort of observation that is generically called an item, it means that there exists (a) a procedure, or design, which allows the observations to be made under a set of standard conditions that span the intended range of the item contexts, and (b) a procedure for classifying those observations into a set of standard categories. The first part is the topic of this chapter, and the second is the topic of the next chapter. The measurement instrument is then a set of these procedures (i.e., a set of items). First, the idea of an item is developed in the section immediately below, and some typical types of items are discussed. Then, a typology of items is introduced that is designed to show connections among many different sorts of items This is followed by a discussion of the important facets of the whole-instrument design. After that, there are section devoted to (a) the inclusion of a fairness perspective into the items design and (b) the incorporation of human judgement into the items design. Finally, ways of developing items are discussed in the last section.  In the next chapter (Chapter 4), this understanding about the nature of the item is complemented to include the way that the observations are recorded and categorized.