Simple Statistics for Correlating Survey Responses

Abstract

The rank-sum test is a non-parametric hypothesis test that can be used to determine if there is a statistically significant association between categorical survey responses provided for two different survey questions. The use of this test is appropriate even when survey sample size is small. The rank-sum test is most useful when the goal is to determine whether two groups of respondents differ in their average response to a particular survey question for which response categories are logically ordered according to magnitude (e.g., Likert-scale responses).