Graziano & Raulin
Research Methods (9th edition)
Manipulation Check
Ordered Data
A manipulation check involves verifying that the independent variable manipulation had the effect that the researcher intended. If the research is not experimental in nature, there will be no manipulation check. Therefore, click the PROCEED button below.
If your manipulation check variable produces ordered data, your manipulation check will normally involve computing frequencies and a nonparametric inferential statistics, such as a Mann-Whitney U-test. Computational procedures for the Mann-Whitney U-test can be found in most undergraduate statistics textbooks. Unfortunately, it can only be used with two groups.
Are there other manipulation-check variables
that should be evaluated?
If so, click the RETURN button.
Otherwise, click the PROCEED button.