ITEM SCALING
Item scaling is a technique used in psychological testing that involves assigning numeric values to individual items on a questionnaire or survey. This is done to measure the responses of participants to each item and to identify patterns in the responses. Item scaling techniques are used to produce reliable and valid data for research purposes, making it an important tool in the field of psychology.
Item scaling techniques are used to measure the degree to which individual items in a questionnaire or survey reflect the overall construct of interest. As such, the technique is used to ensure that the data collected is both reliable and valid. The technique is also used to identify relationships between items and to identify patterns in the responses.
There are three main types of item scaling techniques that are used in psychological testing: Likert scaling, Thurstone scaling, and Guttman scaling. Likert scaling is the most commonly used item scaling technique and involves assigning a numerical rating to each item on a scale. This type of scale is used to measure responses to a single item or a collection of items. Thurstone scaling is used to assess the relative importance of individual items on a scale. This type of scaling is based on the concept of “equal appearing intervals”, which is used to compare the magnitude of responses between items. Guttman scaling is used to identify patterns in responses to a set of items. This type of scale is based on the concept of “nested sets”, which is used to identify clusters of items that reflect similar responses.
Item scaling is an important technique for researchers in the field of psychology. It allows researchers to obtain reliable and valid data from participants that can be used to identify patterns in the responses and understand the underlying construct that is being measured.
References
Fowler, F. J., Jr. (1995). Improving survey questions: Design and evaluation. Newbury Park, CA: Sage.
Guttman, L. (1945). A basis for scaling qualitative data. American Sociological Review, 10, 139-150.
Keller, P. A., & Smith, C. R. (1996). Item scaling in psychological testing. Psychological Assessment, 8(2), 101–110.
Likert, R. (1932). A technique for the measurement of attitudes. Archives of Psychology, 140, 1–55.
Thurstone, L. L. (1927). A law of comparative judgment. Psychological Review, 34, 273–286.