Napping data ara issued from sessions where panelists arrange all the products on a blank paper sheet.
Napping allows to collect directly in only one session the sensory distances panelists perceived between products.
Each panelist discriminates products according to his own criteria.
The closer two products are, the more alike the panelist perceives them.
The data set has as many rows as there are products and 2*number of panelists columns, each pair of columns corresponding to the X and Y coordinates of the products for one panelist.
To analyse such data, SensoMineR provides three functions:
- nappeplot function and nappesortplot function to represent panelists'tableclothes
- indscal function to perform the Indscal model
- pmfa function for Procrustes Multiple Factor Analysis