A multiple-response chi-square framework for the analysis of Free-Comment and Check-All-That-Apply data

International audience; Free-Comment (FC) and Check-All-That-Apply (CATA) provide a contingency table containing citation counts of descriptors by products. The analyses performed on this table are most often related to the chi-square statistic. However, such practices are not well suited because they consider experimental units as being the citations (one descriptor for one product by one subject) while the evaluations (vector of citations for one product by one subject) should be considered instead. This results in incorrect expected frequencies under the null hypothesis of independence between products and descriptors and thus in an incorrect chi-square statistic. Thus, analyses related …

Time periods segmentation in TDS and TCATA

International audience

Sensory evaluation with consumers revisited thanks to Free-Comment

International audience

Free-comment data collection and analysis revisited and new tools in correspondence analysis

International audience; Free-Comment (FC), as a response to open-ended questions, provides sensory descriptions of a set of products with no issue due to a predefined list of descriptors as in Check-All-That-Apply (CATA).Performances (discrimination, characterization, stability, etc.) of the FC methodology as a method of sensory characterization of products have been poorly documented and FC has rarely been compared to other methodologies of sensory characterization. Further, the use of FC is usually restricted to static sensory descriptions of the products with few considerations given to temporal description, hedonic appreciation and drivers of liking.FC data is frequency data and as such…

Attack-Evolution-Finish: a new method allowing for temporal product description thanks to Free-Comment with consumers

Eating chocolate, smelling perfume or watching video advertisement: Does it make any difference on emotional states measured at home using facial expressions?

Type d'article : méthodologie, recherche et revue.; International audience; The recording of facial expressions allows for implicit measurement of emotional states over time. The present study investigated whether these recordings can be acquired, using computer webcams, when testing products at home. Three types of product spaces (chocolates, perfumes and video advertisements) were evaluated at home by 44 subjects using a facial expression measurement protocol. Each product space was composed of three products. The first objective examined the feasibility of such a home-based protocol. The second objective investigated whether several products in the same product space could be characteriz…

Free comment using speech recognition: an alternative to Check-All-That-Apply for sensory characterization of red wines at home

International audience

Sensory analysis with consumers using Free-Comment : analyses, performances and extensions

Free-Comment (FC) consists in panelists describing the products using their own terms. Despite its benefits, notably the circumvention of limitations inherent to pre-established lists of sensory descriptors, FC remains rarely used because its performances are not well documented and its analyses and range of application remain limited. This thesis aims to overpass these limitations, highlighting the benefits and the potency of FC and thus put it in the spotlight for sensory analysis with consumers.For the pretreatment of FC data, a semi-automatized procedure is proposed. It enables the practitioners to extract an a posteriori list of sensory descriptors with a compromise between minimizing …