Use of Shape Preference Information in Product Design

A common trade-off in product design is form versus function. While function is typically analyzed and understood quite well, user preferences for the visual shape of a form are not. Product shape has become an increasingly important market differentiator, and so the need for better shape preference analysis has also increased. Conjoint analysis and PREFMAP are preference assessment techniques that can facilitate the inclusion of shape in a form-function trade-off analysis. This article presents a study that compares PREFMAP and conjoint analysis models based upon the same descriptive input data. Results show that such techniques must be used with great care, lest they fail to capture an actual description of user preference. Next, a conjoint analysis model for shape preference is linked with engineering models of a cola bottle to explore the trade-offs between the bottle’s form and the associated technical functionality.