Design for Behavior Change: The Role of Product Visual Aesthetics in Promoting Sustainable Behavior.

Abstract

This dissertation tested the hypothesis that products can be designed in a principled way to induce users to modify their behavior; in particular, it explored how products make people be more environmentally responsible. Adopting an interdisciplinary approach, we reviewed literature from psychology, human computer interaction, social marketing, and product design to identify a gap in our knowledge, formulate research questions and select paradigms to use in behavioral testing.

Empirical studies were conducted in two parts. Part I consisted of one retrospective study and two case studies based on the Elaboration Likelihood Model of Persuasion. The studies showed that the visual properties of a product influence how it is used and can prompt users to change their behavior to be more environmentally friendly. In the recycling case study (Study 1), more people recycled in a visually salient recycling bin. In the napkin consumption case study (Study 3), patrons of a coffee shop consumed fewer napkins when the napkin dispenser was designed to elicit the metaphor that compared the use of napkins with consuming a tree (55% reduction in use), versus using the original standard dispenser. A retrospective study (Study 2) identified seven persuasive heuristics to help designers use metaphors that promote sustainable behavior. Part II validated these Persuasive Metaphors Heuristics by studying how designers use them, and how they influence design outcomes in terms of persuasiveness, effectiveness, and uniqueness of the concepts. The results indicated that the heuristics increased the persuasiveness of the design concepts. Overall, the dissertation showed that if the designer can identify the right information-processing route (based on behavior, user, and context) and implement the Persuasive Metaphors Heuristics, then the visual appearance of a product can successfully cue desirable behavioral responses. Also, Part II suggested that the heuristics can be taught to novice designers as a tool to narrow down the solution space toward designs with persuasive intent.

This research pursued an evidence-based persuasive approach to understand the link between perceived formal and meaningful properties of design, how users process these properties, and how these product properties influence decision-making and consequent behavioral responses.