Free-choice profiling is a method for determining the quality of a thing by having a large number of subjects experience (view, taste, read, etc.) it and then allowing them to describe the thing in their own words, as opposed to posing them a set of "yes-no-maybe" questions. All of the descriptions are then analyzed to determine a "consensus configuration" of qualities, usually through Generalized Procrustes analysis (GPA) or Multiple factor analysis (MFA). A comparison between GPA and MFA, based on sensory data, is a chapter of a recent book: Pagès Jérôme (2014). Multiple Factor Analysis by Example Using R. Chapman & Hall/CRC The R Series London 272 p
Free-choice profiling first emerged in 1984, but the original published model has been modified by researchers into variations that are more applicable to their particular use. For example, a technique employed by Jean Marc Sieffermann combined it with flash profiling, specifically using the free-profiling strategy of individual panelist vocabulary generation. The method allows panelists to freely develop their own descriptors and scales. A study shows that free-choice profiling can provide more accurate sample maps compared with other methodologies, such as project mapping and free sorting in the area of sensory characterization.
Notes and references
Sources Raw Hop Aroma Qualities by Trained Panel Free-Choice Profiling, Gregory J. Stucky and Mina R. McDaniel, available on-line