La rationalité limitée des consommateurs lors de l'évaluation d'un produit comportant un attribut environnemental : une étude empirique des biais provoqués par le nombre d'attributs et le mode d'évaluation

摘要

Environmental attributes are increasingly being included in consumption products. Because environmental attributes are credence attributes, they refer to a public good (i.e. environmental protection), and they reference moral values, they are difficult for consumers to assess. This doctoral research specifically focuses on how consumers use an environmental attribute (certified or uncertified) in product evaluation. This core question is addressed through three research questions. The first deals with the effect of attribute number (1 vs. 2) on the weight given to environmental attributes. This study focuses on a counterintuitive effect named the embedding effect, characterized by insensitivity to the number of environmental attributes present. The second question concerns the effect of the method of value measurement on the weight given to an environmental attribute. The effects of two criteria are studied: response mode (pricing vs. non pricing) and evaluation mode (joint vs. separate). The third and last question extends the study of evaluation measure and its effect on the weight of an environmental attribute by testing the predictive validity of the evaluation measure on consumer preferences. These research questions are investigated with five experiments that employ various environmental attributes and stimuli. From a theoretical perspective, this research shows the importance of considering the embedding effect and evaluation measurement bias for people interested in environmental attributes evaluation. It also underlines the potential limit of adding an environmental attribute to a consumption product. In terms of utility measurement, the thesis shows, counterintuitively, that willingness to pay is a better measure of environmental values than is choice. From a methodological standpoint, this doctoral thesis proposes an approach to enable attribute weight comparisons across measures. This research suggests to product managers that they need to be aware of these contextual factors when assessing and predicting consumer preferences for a product with an environmental attribute. If the environmental attribute in the finished product will be alone versus in conjunction with another environmental attribute, for example, affects attribute utility. Likewise, willingness to pay appears to be a better predictor of actual preference for environmental attribute than is choice.