Rating scale analysis
In many research studies, respondents' beliefs and opinions about various concepts are often measured by means of five, six and seven point scales. The widely used five point scale is commonly known as a Likert scale (Likert, (1932) "A technique for the measurement of attitudes", Archives of Psychology, 22, No. 140). In such situations, it is desirable to have a test statistic that provides a measure of the amount of agreement or disagreement in the sample, that is, whether or not a particular item 'pole' is characteristic of the respondents. This is preferable to making arbitrary decisions about the extremeness or otherwise of the sample responses. A suitable test for this purpose was designed by Cooper (1976), "An exact probability test for use with Likert-type scales, Educational and Psychological Measurement, 36, pp. 647-655. (Cooper z), with modifications suggested by Whitney (1978), "An alternative test for use with Likert-type scales", Educational and Psychological Measurement, 38, pp. 15-19 (Whitney t). Cooper showed that for large samples, the Cooper z statistic has a sample distribution that is approximately normal. The alternative Whitney t statistic has a sample distribution that is approximately t with (n-1) degrees of freedom and is suitable for small samples. Between them, these two statistics, although rarely used, provide a quick and straightforward way of analysing rating scales in an objective way. This presentation will describe the Stata syntax used to calculate the Cooper z and Whitney t statistics and create the related bar graphs. An illustrative example will be used to demonstrate their use in a survey.
When requesting a correction, please mention this item's handle: RePEc:boc:usug09:09. See general information about how to correct material in RePEc.
For technical questions regarding this item, or to correct its authors, title, abstract, bibliographic or download information, contact: (Christopher F Baum)
If you have authored this item and are not yet registered with RePEc, we encourage you to do it here. This allows to link your profile to this item. It also allows you to accept potential citations to this item that we are uncertain about.
If references are entirely missing, you can add them using this form.
If the full references list an item that is present in RePEc, but the system did not link to it, you can help with this form.
If you know of missing items citing this one, you can help us creating those links by adding the relevant references in the same way as above, for each refering item. If you are a registered author of this item, you may also want to check the "citations" tab in your profile, as there may be some citations waiting for confirmation.
Please note that corrections may take a couple of weeks to filter through the various RePEc services.