Covariance Analysis

The analysis of covariance (ANCOVA) is a statistical technique that combines the methods of analysis of variance (ANOVA) and regression analysis. The main aim of this analysis is to determine if there are significant differences between the means of multiple treatment means while controlling for the effect of one or more continuous variables (called covariates) that could influence the response variable. ANCOVA assumes that relationship between the covariable and the response variable is linear and is the same in the set of treatments. ANCOVA eliminates strange variations that cannot be effectively controlled by the experimental design, and adjusts the treatment means by a common covariate value for fair comparisons.