2.3. Experimental procedure
2.3.1. Purchase approach
Wine shop: A simulated ‘‘wine shop’’ was set up in a room of
‘‘Centre des Sciences du Goût et de l´ Alimentation’’ (CSGA) by using
typical decorating elements such as bottles, wine glasses, pictures
and even a cheque-out-desk in order to create a realistic context.
The 24 wines of the study were presented in four shelves arranged
according to geographic origin as shows Table 2, according to standard
arrangement in French wine shops or supermarkets. To avoid
biassed choices depending on bottle position, bottles were randomly
ordered for each participant on shelves. The position of
the bottles in shelves was also randomly placed for each
participant.
The group of 48 participants was divided in two at random; half
of them carried out the choice experiment and the other half the
auction experiment, both in the simulated wine shop, as explained
below.
Choice experiment: Under this condition, participants simply had
to choose individually the five bottles (out of 24) in the wine shop
that seemed of best quality for them. Making the task more involving
participants were told they would be allowed to keep one of
the bottles selected as an incentive for their participation in the
study and thus granting their choice real consequences. Instructions
given to participants were as follows:
‘‘Welcome to the wine shop of CSGA. Imagine you are here today to
buy five bottles of wine of good quality. Among the 5 bottles you will
choose, we will offer you one. This is to indicate you that you have to
choose the bottles you would really like to taste, to bring home. You
can put the five chosen bottles in this basket, and obviously, you can
examine bottles as you wish. Once you will have finished, you can pass
to the cheque-out-desk’’
Once the participant had finished the task, the experimenter
filled in a voucher for each of the five-chosen bottles by indicating
the price the participant was willing to pay in each case.