Statistics Roundtable: Likert Scales and Data Analyses
- Quality Progress
- July 2007
- Volume 40 Issue 7
- pp. 64-65
- Allen, I. Elaine, Seaman, Christopher
- Babson College, Babson Park, MA, Graduate Center of City University of New York
Likert scales are a common ratings format for surveys. Respondents rank quality from high to low or best to worst using five or seven levels. Your initial analysis of Likert scalar data should not involve parametric statistics but should rely on the ordinal nature of the data. While Likert scale variables usually represent an underlying continuous measure, analysis of individual items should use parametric procedures only as a pilot analysis. Combining Likert scales into indexes adds values and variability to the data. If the assumptions of normality are met, analysis with parametric procedure can be followed. Finally, converting a five or seven category instrument to a continuous variable is possible with a calibrated line or track bar.