Discrimination study of packet soup
soup data frame has 1847 rows and 13 variables. 185
respondents participated in an A-not A discrimination test with
sureness. Before experimentation the respondents were familiarized
with the reference product and during experimentation, the respondents
were asked to rate samples on an ordered scale with six categories
given by combinations of (reference, not reference) and (sure, not
sure, guess) from 'referene, sure' = 1 to 'not reference, sure' = 6.
factor with 185 levels: the respondents in the study.
factor with 2 levels: index reference and test products.
factor with 6 levels: index reference and the five test product variants.
ordered factor with 6 levels: the respondents ratings of soup samples.
factor with two levels: experimentation was split over two days.
factor with three levels: the type of soup regularly consumed by the respondent.
factor with 3 levels: the frequency with which the respondent consumes soup.
factor with two levels: does the respondent have a cold?
factor with ten levels: How easy did the respondent find the discrimation test? 1 = difficult, 10 = easy.
factor with two levels: gender of the respondent.
factor with four levels: the age of the respondent.
factor with three levels: three different locations where experimentation took place.
%% integer vector: the sequence at which experimentation took
%% place. Numbering restarted at the second day of experimentation.
Christensen, R. H. B., Cleaver, G. and Brockhoff, P. B.(2011) Statistical and Thurstonian models for the A-not A protocol with and without sureness. Food Quality and Preference, 22, pp. 542-549.