Showering is one of the most water-intensive behaviours in urban households, accounting for 20–30% of water use. Real-time feedback from smart devices has been proven to significantly reduce water consumption in showers. Still, it is not known whether these devices have spillover effects on other water use behaviours. For the first time, we provide empirical evidence for a significant and negative within-domain spillover effect from the use of such devices, showing an increase in water use in other activities by 2.5% per day per household. Up to one-third of conservation effects are eroded by such spillovers, resulting in a two steps forward, one step back situation. Overall, however, net water use is still reduced by 4.7% in the 385 households that were observed. This study points out an important behavioural limit on the use of such smart shower devices and suggests that such use be accompanied by informational or other campaigns to reduce the large negative spillovers.

Nudging is often proposed as a promising policy approach for improving healthy choices among lower socioeconomic position (SEP) populations. However, nudges may not suit lower SEP contexts and empirical studies are scarce. We examined the efficacy of a repositioning nudge at a supermarket in a deprived neighborhood in improving healthier snack purchases and described customers’ healthy grocery shopping needs. Daily sales were collected during 4-week control and intervention periods, where healthier snacks replaced unhealthy snacks at the checkout. Besides, questionnaires were administered. More healthier snacks were sold per day during the intervention (Median = 2.50, Q1 = 2.00, Q3 = 3.50) than control period (Median = 0, Q1 = 0, Q3 = 1.00), B = 1.77, z = 5.50, p < .001, incidence rate ratio = 5.87 (95%CI [3.52, 10.17]). Despite statistical significance, the absolute number of healthier snacks sold remains negligible. Customers report to find it important to eat healthily and to think carefully about their groceries, but to hardly buy snacks at the checkout and desire a healthy and affordable food offer. Repositioning nudges may not suit the circumstances and needs of lower SEP populations. Interventions must be tailored to lower SEP groups and integrated with system-level policies.

Existing regulation in the UK states that the term ‘milk’ can only be used in labelling to describe products that originate from animals. We conducted an observational study, which surveyed the availability and labelling of milk substitutes in UK supermarkets, and an online experimental study, which assessed the impact of using the term ‘milk’ on milk substitute labelling. In the experimental study, 352 UK adults were randomised to one of the two conditions where they saw milk substitutes that were either labelled with UK regulations (e.g., soya drink) or using the term ‘milk’ (e.g., soya milk). Our primary aims were to assess whether adding the term ‘milk’ to labels would (1) more accurately communicate the uses of milk substitutes or (2) confuse consumers about which products come from an animal source. In our observational study, milk substitutes were readily available and labelling varied significantly. In our experimental study, labelling products with the term ‘milk’ increased understanding of the product's use. However, participants who saw the term ‘milk’ on milk substitute labelling misidentified more milk substitutes as coming from an animal source. Future policy should consider the clarification of such labelling.

To what extent can the harms of misinformation be mitigated by relying on nudges? Prior research has demonstrated that non-intrusive ‘accuracy nudges’ can reduce the sharing of misinformation. We investigate an alternative approach. Rather than subtly reminding people about accuracy, our intervention, indebted to research on the bystander effect, explicitly appeals to individuals' capacity to help solve the misinformation challenge. Our results are mixed. On the one hand, our intervention reduces the willingness to share and believe in misinformation fact-checked as false. On the other hand, it also reduces participants' willingness to share information that has been fact-checked as true and innocuous, as well as non-fact-checked information. Experiment 1 offers proof of concept; Experiment 2 tests our intervention with a more realistic mix of true and false social media posts; Experiment 3 tests our interventions alongside an accuracy nudge. The effectiveness of our intervention at reducing willingness to share misinformation remains consistent across experiments; meta-analysis reveals that our treatment reduced willingness to share false content across experiments by 20% of a scale point on a six-point scale. We do not observe the accuracy nudge reducing willingness to share false content. Taken together, these results highlight the advantages and disadvantages of accuracy nudges and our more confrontational approach.

Littering involves throwing away waste in places not designated for it, harming the environment. This study introduces a strategy to encourage more use of Littergram, an app designed to fight littering. Littergram allows users to photograph litter and share these images publicly, alerting local councils to clean up the waste. The study aimed to increase user engagement with Littergram by implementing an intervention designed using the Behaviour Change Wheel (BCW), a comprehensive framework for developing behaviour change interventions. We developed and applied a digital campaign through emails, following BCW guidelines. The process began with identifying the behaviour we wanted to change. We conducted a survey to understand what influences this behaviour and selected techniques for changing behaviour based on these insights. The campaign involved sending targeted emails to Littergram users. There was an increase in the use of Littergram during the campaign, and growth returned to initial levels after the campaign ended. This outcome shows that the approach can effectively increase engagement temporarily. Future research should focus on challenges in maintaining long-term behaviour change.

Nudges are widely employed tools within organizations, but they are often criticized for harming autonomy and for being ineffective. We assess these two criticisms simultaneously: can nudges be both autonomy-preserving and effective in changing behavior? We developed three nudges – an opinion leader nudge, a rule-of-thumb and self-nudges – to reduce a particularly sticky behavior: email use. In a survey experiment of 4,112 healthcare employees, we tested their effect on perceived autonomy and subjective effectiveness. We also tested traditional policy instruments for comparison. Next, to assess objective effectiveness, we conducted a quasi-field experiment in a large healthcare organization with an estimate of 1,189 active email users. We found that each nudge in isolation, but especially when combined, was perceived to be both autonomy-preserving and effective, and more so than traditional policy instruments like an access limit or a monetary reward. We also found some evidence that the combination of all nudges decreased actual email use. This paper advances the literature by showing how innovations in nudge design improve nudges’ ability to be autonomy-preserving and effective.

To improve public health and promote environmental sustainability, widespread dietary changes are necessary in high-income countries. However, adopting and maintaining dietary goals is challenging and requires repeated self-regulation. Effective public policies can facilitate healthy food choices and reduce the likelihood of goal failure. This study examines the relationship between individuals’ dietary goal failures and their acceptance of public food policies, using data from an experience-sampling study (Ni = 409 and Nobs = 6,447). Regression analyses revealed that participants who experienced more frequent dietary goal failures were generally less accepting of health-promoting food policies and perceived them as less effective. Additionally, perceived policy effectiveness positively predicted policy acceptance. Exploratory analyses showed that the negative relationship between dietary goal failure and food policy acceptance varied depending on the type of intervention (pull policies vs push policies) and the location of food selections (home vs out-of-home). Notably, we found a positive relationship between dietary goal failure and acceptance of pull policies for food selections made out-of-home. These findings highlight the importance of better understanding the complex interplay between public policy attitudes, the food environment and adherence to dietary goals.

This study investigates the impacts of behavioral finance on stock market volatility. The primary aims are to explain the reasons behind changes in the S&P 500 price within the context of behavioral finance and to analyze investor behavior in response to these changes. To achieve this, the research employs time-series analysis over a 10-year period, focusing on the S&P 500, real interest rates, consumer confidence, market volatility and credit default swaps while considering the effects of behavioral biases. The findings reveal several significant correlations: rising real interest rates negatively affect stocks due to loss aversion and sentiment. Conversely, higher consumer confidence tends to positively influence the stock market, driven by herding behavior and optimism. Additionally, market volatility shows a negative correlation with the S&P 500, influenced by risk aversion, recency bias and herding behavior. Moreover, an increase in credit default swap rates leads to stock market declines, primarily influenced by risk perception, loss aversion and herding behavior.

Traditionally, corruption is seen as a rational pursuit of profit, focusing on personal gain. However, this view overlooks other influences. This paper focuses on the behavioral aspects of corruption, providing a deeper understanding of its complexities, and addressing the factors overlooked by conventional approaches. Reviewing some of the literature, we highlight how researchers have approached corruption from the perspective of behavioral sciences. Additionally, we examine how the emerging discipline of Behavioral Public Policy (BPP) employs innovative methods to reduce corrupt practices, offering new strategies that transcend traditional perspectives. Our paper innovates by demonstrating how corruption can be reduced by substituting traditional regulations with nonregulatory tools like nudges and sludge audits, or by leveraging digital choice architectures to minimize human-to-human interactions, known corruption enablers. By reducing regulations and administrative red tape, and introducing digital frameworks, these tools simplify processes minimizing opportunities for corrupt behavior. In this paper, we aim to infuse corruption research with a behavioral twist, a digital approach, and a deregulatory perspective, offering policymakers an alternative path to foster transparency, accountability and ethical governance. While this approach will not completely eradicate corruption, it strives to show how BPP can reduce its occurrences.

Political scientists have proposed that party cues can be used to compensate for the public's well-documented lack of substantive political knowledge, but some critics have argued that applying party cues is more difficult than assumed. We argue that this debate has proven intractable in part because scholars have used ambiguous normative criteria to evaluate judgments. We use a unique task and clear normative criteria to evaluate the use of party cues in making political judgments among two samples: a sample of state legislators and an online sample of the public. We find that the public sample performs poorly when using cues to make judgments. State legislators make much more accurate judgments on average than even the most attentive segment of the public and are more likely to place less weight on irrelevant cues when making judgments, although there is evidence that both samples performed worse with the inclusion of non-diagnostic cues. We conclude with a discussion of the relevance of the results, which we interpret as showing that party cue use is more difficult than theorized, and discuss some practical implications of the findings.

Consequentialist theories of the behavioral state are largely grounded in satisfying self-interested preferences through policies that employ choice architecture and related strategies to encourage rational decision-making. Even when allowing for free choice, however, this stance tends to be characterized by a paternalistic ‘view from nowhere’ that may not fully accommodate a plurality of values. Alternative approaches such as contractarianism position policy in the context of marketplace exchange, bolstered by shared beliefs in the legitimacy of social institutions. Yet this view may not sufficiently consider issues of asymmetric access, or ideological frames that do not see these institutions as legitimate. To address these deficits, we propose the value of a dialogical approach to behavioral public policy that facilitates collaborative engagement and behavioral justice to redress asymmetries and inequities through a more discursive approach, which builds on practices employed by design for public policy. In so doing, this political theory suggests an actionable counterpoint to paternalistic and competition-based conceptions of the State to address frame plurality and increase the potential for system equity.

Possibly the most important argument for the permissibility of choice architecture is the inevitability argument (IA), which states that if choice contexts are to inevitably influence individuals in some way, they should be arranged to best promote their welfare. Opponents point out a moral difference between influence from unmodified environments (including environments designed without any thought given to behavioral influence) and environments modified specifically to produce behavioral effects. Only the latter are said to subvert the will of those affected, and thereby raise concerns pertaining to manipulation, mistreatment of rational agency, etc. We argue, however, that if choice architects can reliably predict the behavioral effects of both the unmodified environment and available alternatives, the moral difference between these environments seems insignificant. In such cases, one version of the IA persists. This version establishes the permissibility of choice architecture in circumstances of reliable prediction, but is itself neutral toward available normative directions.

Following the growing interest in using behavioral theory and choice architecture in the public sector, several new studies have looked at how changes in the choice architecture of budget simulations influence the participants’ budgetary decisions. These studies have also introduced the possible problem that participants may make inappropriate choices in the budget simulation, like creating a budget with unacceptably high budget surpluses. Building on Thaler and Sunstein’s NUDGES framework, we seek to answer the question, ‘How can budgetary choice architects correct for errors such as large ending surpluses at the end of the budget simulation?’ We replicate earlier results on budget starting conditions. Additionally, we test a budget treatment that encourages participants to reduce ending budget surpluses. The budget treatment works as intended and suggests that the large ending budget surpluses stem from errors made by participants in the simulation rather than loss aversion. The need to both nudge and budge participants is important for practicing choice architects, like public budgeters who have to design and implement tools that inform citizens and reveal accurate preferences that conform with legal requirements.

Similarly to other domains of the social sciences, behavioural science has grappled with a crisis concerning the effect sizes of research findings. Different solutions have been provided to answer this challenge. This paper will discuss analytical strategies developed in the context of computational social science, namely causal tree and forest, that will benefit behavioural scientists in harnessing heterogeneity of treatment effects in RCTs. As a mixture of theoretical and data-driven approaches, these techniques are well suited to exploit the rich information provided by large studies conducted using RCTs. We discuss the characteristics of these methods and their methodological rationale and provide simulations to illustrate their use. We simulate two scenarios of RCTs-generated data and explore the heterogeneity of treatment effects using causal tree and causal forest methods. Furthermore, we outlined a potential theoretical use of these techniques to enrich behavioural science ecological validity by introducing the notion of behavioural niche.

Dark patterns are user interface design elements which harm users but benefit vendors. These harms have led to growing interest from several stakeholders, including policymakers. We develop a high-level analytical framework – the dark patterns auditing framework (DPAF) – to support policymaker efforts concerning dark patterns. There are growing links between dark patterns and the behavioural science concept of sludge. We examine both literatures, noting several worthwhile similarities and important conceptual differences. Using two ‘sludge audits,’ and the DPAF, we examine 14 large online services to provide a high-level review of the user experience of these services. Our approach allows policymakers to identify areas of the user ‘journey’ (dark paths) where sludge/dark patterns persist. For regulators with constrained resources, such an approach more be advantageous when planning more granular analyses. Our approach also reveals several important limitations, notably, within some of the tools for sludge auditing which we develop, such as the ‘equal clicks principle.’ We discuss these limitations and directions for future research.

System change and individual behavior change are often conceptualized as contrasting, mutually exclusive strategies for climate change mitigation, with system change usually considered more powerful, direct or urgent. We argue that this alleged duality is misguided and that system change and behavior change are fundamentally co-dependent: system change is often effective to the extent that it promotes individual behavior change and, vice versa, individual behavior change contributes to the critical mass that is needed to spur system change. We map four pathways that link behavior change and system change, driven by consumer activism, consumer demands, policies that address people as part of a community and the provision of collective action arrangements. Together, these pathways illustrate that system and behavior change are often interconnected and suggest promising avenues for developing climate mitigation policies that jointly promote system and behavior change.

The purpose of this paper is to first review William James's explicit positions on paternalism in the context of medical licensure and the annexation of the Philippines. Then I wish to show that these positions, as well as a more generalized antipaternalist stance, are the implications of James's philosophy and psychology and not simply his ‘personal’ sentiments. The elements of James's thought are arranged in such a way as to facilitate a comparison with contemporary behavioral (heuristics and biases) paternalism. The conclusion is that James has arguments against behavioral paternalism avant la lettre that are still useful and deserve discussion.

Indoor air pollution is one of the leading causes of morbidity and mortality worldwide, but its sources and impacts are largely misunderstood by the public. In a randomised controlled trial including 281 households in France, we test two interventions aimed at changing indoor polluting behaviour by raising households’ awareness of health risks associated with indoor air pollution. While both generic and personalised information increased knowledge, only personalised information including social comparison feedback changed behaviour, leading to a reduction of indoor PM2.5 (particulate matter with an aerodynamic diameter ≤2.5 µm) emissions by 20% on average. Heterogeneous treatment effects show that this effect is concentrated on the most polluted households at baseline, for whom the reduction reaches 40%.

There are both negative and positive stereotypes about public sector workers. Most studies focus on negative stereotypes, like the idea that public servants are lazy. We, however, do the opposite. We focus on a positive stereotype: public sector workers are seen as caring and helpful. We test the effects of positive stereotypes on the quality of public service delivery. Using a pre-registered audit experiment in elderly care in the Netherlands and Belgium, we find that activating a pro-social stereotype does not affect the outcome of public service quality in terms of response rate and information provision. However, it does improve the bureaucratic process: public sector workers are friendlier toward citizens. They say around 12% more ‘thank you’ in their replies. Moreover, the citizens’ gender affects the response rate: female citizens receive around 10% more replies. Concluding, we show that positive stereotyping can improve parts of the quality of public service delivery but not all.

Our daily lives are shaped by the digital platforms we engage with, presenting both challenges and opportunities in the pursuit of health and social well-being. Despite extensive public efforts to increase physical activity, sedentary lifestyles and car-dependence persist; often exacerbated by digital apps functioning at odds with these initiatives. With growing urbanization, walking for transportation becomes a feasible way for many Americans to achieve daily activity goals. This work explores the potential of leveraging nudges within digital apps, specifically Google Maps, to encourage walking. I found that displaying walking directions as the default in Google Maps, instead of driving, and complemented by graphics depicting social norms, significantly increased the hypothetical choice to walk — particularly among less active individuals. This underscores the power of digital environments in shaping our choices and outcomes; and highlights the need for us to critically assess digital app design. I advocate for collaboration between ‘big tech’, policymakers, and the public to create digital tools that balance our immediate convenience with long-term health and environmental sustainability goals. Re-envisioning technology’s role in daily life, we can potentially harness its vast influence to foster choices that contribute to both personal well-being and the collective good.