Generalized Procrustes analysis (GPA) is a method of statistical analysis that can be used to compare the shapes of objects, or the results of surveys, interviews, or panels.
It was developed for analysing the results of free-choice profiling, a survey technique which allows respondents (such as sensory panelists) to describe a range of products in their own words or language.
GPA is one way to make sense of free-choice profiling data;[1] other ways can be multiple factor analysis (MFA),[2][3] or the STATIS method.
Unlike measures such as a principal component analysis, GPA uses individual level data and a measure of variance is utilized in the analysis.
The Procrustes distance provides a metric to minimize in order to superimpose a pair of shape instances annotated by landmark points.