Multivariate analysis of covariance (MANCOVA) is a statistical technique that is the extension of analysis of covariance (ANCOVA). Basically, it is the multivariate analysis of variance (MANOVA) with a covariate(s).). In MANCOVA, we assess for statistical differences on multiple continuous dependent variables by an independent grouping variable, while controlling for a third variable called the covariate; multiple covariates can be used, depending on the sample size. Covariates are added so that it can reduce error terms and so that the analysis eliminates the covariates’ effect on the relationship between the independent grouping variable and the continuous dependent variables.. Questions answered:
Do the various school assessments vary by grade level after controlling for gender?
Do the rates of graduation among certain state universities differ by degree type after controlling for tuition costs?
Which diseases are better treated, if at all, by either X drug or Y drug after controlling for length of disease and participant age?
In multivariate analysis of covariance (MANCOVA), all assumptions are the same as in MANOVA, but one more additional assumption is related to covariate:
Key concepts and terms:
*For assistance with conducting a MANCOVA or other quantitative analyses click here.
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