Using framing effects to inform more sustainable infrastructure design decisions

Decision aids, ranging from rating systems to design software to regulatory standards, guide the design and evaluation of infrastructure projects. To present the information in these decision aids, there must first be some options such as, attributes are or are not presented, and, just as in other domains, these factors are likely to influence decisions in infrastructure development. The authors of this paper seek to better understand how choice structures influence engineering decisions. Prospect theory, which is well established in the behavioral sciences, asserts that people tend to think of possible outcomes relative to their starting point, not the resulting end point. For instance, framing a decision outcome as a loss in value (rather than a gain) can reduce the decision makers' acceptance of risk and, in turn, lead to more conservative outcomes. To measure framing effects in engineering decisions, this paper uses the Envision rating system for sustainable infrastructure, which aims to help civil engineers achieve the highest feasible sustainability performance in their projects. The hypothesis is that Envision's framework inadvertently limits the likelihood that engineers will set the highest achievable goals for sustainability. In the current framework, engineers start with zero points and achieve points when design considerations move beyond conventional construction standards. In this modified experimental version, a higher benchmark is set. Engineers are endowed points and can lose them for not maintaining high goals for sustainability. Engineering professionals (n=65) used Envision to make tradeoffs about site programming and functionality for a rural redevelopment project. Participants were randomly assigned the standard version (n=33) or the experimental version (n=32). The experimental group achieved 66% of points compared with the standard group's 51% (p<0.01). These results indicate that a choice posed as a loss rather than a gain significantly improved engineers' consideration for sustainability achievement. The findings suggest the need for more thoughtfully designed decision aids, with guidance from established behavioral science. This type of interdisciplinary research holds the potential to yield relatively low-cost solutions that support greater sustainability in infrastructure development.