Infrastructure decisions, at the societal, organizational and individual scale, often rely on social heuristics or rules of thumb to improve design decision outcomes. However, when these heuristics do not align with reality or between stakeholder groups these tactics can lead to less than sustainable outcomes in which buildings and infrastructure are designed in isolation. Buiten and Hartmann [
73] point out that cognitive bias within public–private partnerships can lead to prematurely narrowing project scope and look to research in judgment and decision-making for a solution. Levitt et al. [
74] observe the disconnect between a private–public partnership and its network and emphasize the importance of more research on stakeholder engagement within these partnerships. Research goals such as these can be expanded with aims to encourage whole systems design, meaning, employing systems thinking during the design and construction process to realize the interconnectedness between the systems the design will influence and make changes in order to increase the sustainability of the design or project. By better understanding the influences on decision-making from a choice architecture point of view, researchers can develop interventions to encourage a whole systems design perspective and in turn lead to more sustainable design outcomes. The focus of this section is the decision-making process of infrastructure design and points where manipulating choice architecture encouraged more sustainable outcomes.
6.2. Examples of Choice Architecture Interventions
Empirical research involving interventions within decision aids for infrastructure are known to influence the decision-making process of infrastructure design. Examples include studies testing the effect of role models, framing effect, anchoring bias, and the coupling of multiple choice architecture interventions.
An empirical study tested the effect that a role model project would have on the consideration of sustainability by professional engineers. The role model project illustrated the feasibility of high levels of sustainable achievement. By manipulating Envision, a rating system for sustainable infrastructure [
77], providing a positive role model, illustrating high levels of achievement, led engineering professionals to believe their projects could also meet a higher sustainability performance while a negative role model led to decreased performance when compared to a control group with no role model [
22].
Using a role model as an intervention within a decision aid such as Envision is a form of choice architecture. The study manipulated the presentation of design options and influenced what professional engineers believed was possible, in turn, helping them set realistic but higher sustainability goals.
A more nuanced approach using choice architecture is framing decision outcomes as a loss in value (rather than a gain), which can increase a decision-makers’ acceptance of risk and lead to high goals for achievement. Researchers can make accurate predictions about decision-making based on framing effects [
78] and loss aversion [
79] due to the last 30 years of research [
65]. An example of framing effects and loss aversion applied to infrastructure decisions is another empirical study using the rating system for sustainable infrastructure, called Envision. The study concluded that by endowing points to professional engineers in the sustainable rating system significantly influenced their decision-making. Professional engineers endowed points (with the option to lose points rather than gain them) set high achievement levels goals for sustainability [
62].
Of course, infrastructure decisions are subject to varying constraints, goals, and resources with different stakeholder mandates and budget cycles. Decisions about infrastructure are made in groups. Coupling the role model and framing effect in a group setting using Envision led to similar effects as individual decision-making. This study also showed that disclosing the interventions to participants did not curtail the effect of choice architecture on decision-makers considerations for sustainability [
80].
Just as role model projects illustrate high levels of sustainability and framing effects take advantage of loss aversion, which can improve decision-making, anchoring bias can hinder decision-making for sustainability. Anchoring bias is the tendency of decision-makers to base their decisions off of a predefined standard whether or not it is representative of reality, which could fall under the previously discussed category of bounded rationality [
81]. Anchoring bias in regards to energy performance goals for U.S. buildings was tested in an empirical study with owner representatives from the United States Green Building Council finding that building rating systems can unintentionally result in lower energy performance goals depending on the anchor used to set these energy use reduction goals [
82]. This is relevant because when it comes to the choice architecture of decision aids in infrastructure engineers may adjust their goals based on the initial anchor that they are presented. For example, the American Society of Heating, Refrigerating, and Air Conditioning Engineers (ASHRAE) establishes a 30% minimum energy reduction as a target for future building codes [
82]. This 30% can act as an anchor for building energy goals based. Setting a higher energy reduction target may increase the average energy goal set by building owners.
Not only are decisions about energy and sustainability influenced by choice architecture but also decisions about contract pricing. A study involving civil engineering students tested the coupling of multiple choice architecture methods: reordering criteria, the insertion of emoticons, and explicit examples of risk and uncertainty, within a preliminary design trade-off matrix with aims to increase the attractiveness of particular design options that were defined to be less risky than an alternative [
83]. Although the results of the study were inconclusive, a similar experiment with a larger sample size may hold significant results.
This merging of theories from behavioral science with infrastructure design and construction holds promise to aid in making complex decisions. Choice architecture clearly exists throughout the infrastructure design and construction process and intentional or not, decision-makers are influenced by the way information is presented to them. While our goal is to encourage the use of whole systems design during building and infrastructure design, this approach can be leveraged towards other outcomes as well. The next section details the need for more research in this area, in effort, to take full advantage of the potential of intentional choice architecture.