For such purposes investigators all too commonly categorize (e.g., dichotomize or trichotomize
) a predictor variable and then apply ANOVA.
Generally, multiple bivariate correlation is used to assess the hypothesized association, although some authors dichotomize or trichotomize
the self-report measures of mental imagery and perform multiple t- and F-tests (e.g.
Professor Rakove's essay serves as a useful beginning, since it struggles with the same conceptual problems that have led me to trichotomize
legal change into ordinary, unconventional, and totalizing varieties.
If one wishes to trichotomize
, the middle group can serve, potentially, as neutral comparison group, but only if the distribution makes it truly neutral.