With closed-ended questions, there are a fixed number of response alternatives. In public opinion surveys, a simple “yes or no” or “agree or disagree” dichotomy is often sufficient. In other research, it is often preferable to provide more quantitative distinctions—for example, a 5- or 7-point scale ranging from strongly agree to strongly disagree or very positive to very negative. Such a scale might appear as follows:
Strongly agree _____ _____ _____ _____ _____ _____ _____ Strongly disagree
Rating scales such as the one shown above are very common in many areas of research. Rating scales ask people to provide “how much” judgments on any number of dimensions—amount of agreement, liking, or confidence, for example. Rating scales can have many different formats. The format that is used depends on factors such as the topic being investigated. Perhaps the best way to gain an understanding of the variety of formats is simply to look at a few examples. The simplest and most direct scale presents people with five or seven response alternatives with the endpoints on the scale labeled to define the extremes. The response choices might be lines to mark on a paper Page 140questionnaire, check boxes, or radio buttons in an online survey form. For example,
Students at the university should be required to pass a comprehensive examination to graduate.
How confident are you that the defendant is guilty of attempted murder?
Graphic rating scale A graphic rating scale requires a mark along a continuous 100-millimeter line that is anchored with descriptions at each end.
A ruler is then placed on the line to obtain the score on a scale that ranges from 0 to 100.
Semantic differential scale The semantic differential scale is a measure of the meaning of concepts that was developed by Osgood and his associates (Osgood, Suci, & Tannenbaum, 1957). Respondents are asked to rate any concept—persons, objects, behaviors, ideas—on a series of bipolar adjectives using 7-point scales, as follows:
Research on the semantic differential shows that virtually anything can be measured using this technique. Ratings of specific things (marijuana), places (the student center), people (the governor, accountants), ideas (death penalty, marriage equality), and behaviors (attending church, using public transit) can be obtained. A large body of research shows that the concepts are rated along three basic dimensions: the first and most important is evaluation (e.g., adjectives such as good–bad, wise–foolish, kind–cruel); the second is activity (active–passive, slow–fast, excitable–calm); and the third is potency (weak–strong, hard–soft, large–small).
Nonverbal scales for children Young children may not understand the types of scales we have just described, but they are able to give ratings. Think back to the example in Chapter 4 (page 75) that uses drawings of faces to aid Page 141in the assessment of the level of pain that a child is experiencing. Similar face scales can be used to ask children to make ratings of other things such as a toy.