L'effetto della combinazione di attributi nei processi di formazione di liste brevi (shortlisting)

In this paper we empirically study the effect of a process of evaluation by attributes as part of a decision process in which consumers first use a simple method for shortlisting, then proceed with a closer inspection of a restrict number of alternatives. Shortlisting is based on an incomplete description of the attributes of an alternative. We particularly focus on the presentation of pairs of attributes. The mathematical framework we used is the noncommutative harmonic analysis. The use of this analysis to decompose data on preferences is totally new. We tested the method on data collected through an ad hoc survey. Thanks to this powerful machinery we were able to identify the attraction single attribute has, from the effect of their combination. In particular, the decomposition underlines two effects that we call the first and second order effect. The first order effect measures the average attraction that a single feature has when it is coupled with a second. The second order effect detects the positive (or negative) power of combination that two paired attributes have in driving potential consumers choice. After a brief survey of the general features of our survey, we present in detail two particular cases: the choice of a car and the choice of a personal computer. A particular emphasis will be given to gender differences in the evaluation of car attributes and to the employment position in the evaluation of a personal computer.