3. Explore Various Rating Scales
3.3 Verbal descriptor scales including the Likert scale
As explained in the previous section, numerical rating scales present numerical values for respondents to choose from, while verbal descriptor scales use short verbal phrases as the response options.
Verbal descriptor scales are typically ordinal in nature and can be displayed either horizontally or vertically. Numeric values may be added next to the descriptive terms for codification purposes; however, this does not automatically make the scale an interval scale. That said, some verbal descriptor scales may still be treated as interval scales during data analysis, depending on the context and assumptions.
| ○ Significant improvement needed (1) |
○ Some improvement needed (2) |
○ Met expectations (3) |
○ Exceeded expectations (4) |
○ Not applicable |
|---|---|---|---|---|
| ○ Poor (1) |
○ Fair (2) |
○ Good (3) |
○ Very good (4) |
○ Excellent (5) |
Verbal descriptor scales, as shown in the two examples above, can be bipolar (e.g., job knowledge) or unipolar (e.g., quality). A common type of bipolar verbal descriptor scale is the Likert scale. Rensis Likert, an American social psychologist, first introduced a five-point psychometric scale for measuring a series of attitude-related propositions in the 1930s (Likert, 1932[1]). The wording used in the initial Likert scale was: Strongly Approve, Approve, Undecided, Disapprove, and Strongly Disapprove. Over time, the wording evolved from Approve to Agree, resulting in the Likert scale we know today: Strongly Agree and Agree on one side, Disagree and Strongly Disagree on the other side, and a midpoint in the middle.
Although originally a 5-point scale, the Likert scale has been adapted into various formats, including odd-numbered (e.g., 7-point) and even-numbered (e.g., 4- or 6-point) versions. Even-numbered Likert scales omit a midpoint to encourage a more decisive response. Both odd- and even-numbered versions are discrete rating scales, offering a limited set of fixed response options.
| 4-point Likert scale | 5-point Likert scale | 6-point Likert scale | 7-point Likert scale |
|---|---|---|---|
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There are also Likert-type rating scales that measure aspects other than agreement—such as satisfaction, likelihood, importance, or quality. For example, the perceived quality of service can be measured with the following Likert-type scale that asks how dissatisfied or satisfied customers feel.
| ○ Very dissatisfied |
○ Somewhat dissatisfied |
○ Neutral |
○ Somewhat satisfied |
○ Very satisfied |
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- Likert, R. (1932). A technique for the measurement of attitudes. In R. S. Woodworth (Ed.), Archives of Psychology (Vol. 22, No. 140, pp. 5-55). The Science Press. ↵
