IDEAS home Printed from
   My bibliography  Save this paper

Rating scale analysis


  • Michael Glencross

    () (Community Agency for Social Enquiry, Johannesburg)


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.

Suggested Citation

  • Michael Glencross, 2009. "Rating scale analysis," United Kingdom Stata Users' Group Meetings 2009 09, Stata Users Group.
  • Handle: RePEc:boc:usug09:09

    Download full text from publisher

    File URL:
    File Function: presentation slides
    Download Restriction: no

    More about this item

    NEP fields

    This paper has been announced in the following NEP Reports:


    Access and download statistics


    All material on this site has been provided by the respective publishers and authors. You can help correct errors and omissions. 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). General contact details of provider: .

    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.

    We have no references for this item. You can help adding them by using 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 RePEc Author Service 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.

    IDEAS is a RePEc service hosted by the Research Division of the Federal Reserve Bank of St. Louis . RePEc uses bibliographic data supplied by the respective publishers.