Interventions that tackle ‘last mile’ behaviors in the form of improved choice architecture are fundamental to Behavioral Public Policy (BPP), yet far less attention is typically paid to the nature and design of underlying system conditions and infrastructures that support these interventions. However, inattention to broader conditions that impact participant engagement and intervention functionality, such as barriers to access that deter participation or perverse structural disincentives that reward undesirable behaviors, may not only limit the effectiveness of behavioral solutions but also miss opportunities to deliberately design underlying ‘plumbing’ – the choice infrastructure – in a way that improves overall system efficacy and equity. Using the illustrative case of civic policy in food licensure, this article describes how using a ‘SPACE’ model to address Standards, Process mechanics and policies, Accountability, Culture within systems, and Evaluative and iterative feedback can support the development of improved choice infrastructure, contributing to BPP problem-solving efforts by helping practitioners create system conditions that are more conducive to the success of behavioral solutions.

Many proponents of behavioural public policy work within a broadly consequentialist framework. From this perspective, the ultimate aim of public policy is to maximise utility, happiness, welfare, the satisfaction of preferences, or similar; and the behavioural aspect of public policy aims to harness a knowledge of human psychology to make this maximisation more effective. In particular, behavioural insights may be crucial to help policy-makers ‘save us from ourselves’ by helping citizens avoid falling into non-rational choices, for example, through framing effects, failures of will-power, and so on. But an alternative reading of the psychological literature is that human thoughts and actions are not biased from a rational standard, but are simply systematically inconsistent. If so, then utility and similar notions are not well defined either for individuals or as an objective of public policy. I argue that a different, contractarian viewpoint is required: that the determination of public policy is continuous with the formation of agreements we make with each other at all scales, from momentary social interactions, to linguistic and social conventions, to collective decisions by groups and organisations. Behavioural factors do not over-ride, but can (among many other factors) inform, our collective decision-making process. The point of behavioural insights in public policy is primarily to inform and enrich public debate when deciding the rules by which we should like to live.

Self-control failure occurs when an individual experiences a conflict between immediate desires and longer-term goals, recognises psychological forces that hinder goal-directed action, tries to resist them but fails in the attempt. Behavioural economists often invoke assumptions about self-control failure to justify proposals for policy interventions. These arguments require workable methods for eliciting individuals’ goals and for verifying occurrences of self-control failure, but developing such methods confronts two problems. First, it is not clear that individuals’ goals are context-independent. Second, facing an actual conflict between a desire and a self-acknowledged goal, a person may consciously choose not to resist the desire, thinking that spontaneity is more important than self-control. We address these issues through an online survey that elicited individuals’ self-reported judgements about the relative importance of self-control and spontaneity in conflicts between enjoyment and health-related goals. To test for context-sensitivity, the judgement-elicitation questions were preceded by a memory recall task which directed participants’ attention either to the enjoyment of acting on desires or to the satisfaction of achieving goals. We found little evidence of context-sensitivity. In both treatments, however, judgements that favoured spontaneity were expressed with roughly the same frequency and strength as judgments that favoured self-control.

Despite widespread recognition that behavioral public policy (BPP) needs to move beyond nudging if the field is to achieve more significant impact, problem-solving approaches remain optimized to achieve tactical success and are evaluated by short-term metrics with the assumption of stable systems. As a result, current methodologies may contribute to the development of solutions that appear well formed but become ‘brittle’ in the face of more complex contexts if they fail to consider important contextual cues, broader system forces, and emergent conditions, which can take three distinct forms: contextual, systemic, and anticipatory brittleness. The Covid-19 pandemic and vaccination rollout present an opportunity to identify and correct interventional brittleness with a new methodological approach – strategic BPP (SBPP) – that can inform the creation of more resilient solutions by embracing more diverse forms of evidence and applied foresight, designing interventions within ecosystems, and iteratively developing solutions. To advance the case for adopting a SBPP and ‘roughly right’ modes of inquiry, we use the Covid-19 vaccination rollout to define a new methodological roadmap, while also acknowledging that taking a more strategic approach may challenge current BPP norms.

Recent work by Kahan et al. (2017) on the psychology of motivated numeracy in the context of intracultural disagreement suggests that people are less likely to employ their capabilities when the evidence runs contrary to their political ideology. This research has so far been carried out primarily in the USA regarding the liberal–conservative divide over gun control regulation. In this paper, we present the results of a modified replication that included an active reasoning intervention with Western European participants regarding both the hierarchy–egalitarianism and individualism–collectivism divides over immigration policy (n = 746; considerably less than the preregistration sample size). We reproduce the motivated numeracy effect, though we do not find evidence of increased polarization of high-numeracy participants.

Policy decisions have vast consequences, but there is little empirical research on how best to communicate underlying evidence to decision-makers. Groups in diverse fields (e.g., education, medicine, crime) use brief, graphical displays to list policy options, expected outcomes and evidence quality in order to make such evidence easy to assess. However, the understanding of these representations is rarely studied. We surveyed experts and non-experts on what information they wanted and tested their objective comprehension of commonly used graphics. A total of 252 UK residents from Prolific and 452 UK What Works Centre users interpreted the meaning of graphics shown without labels. Comprehension was low (often below 50%). The best-performing graphics combined unambiguous metaphorical shapes with color cues and indications of quantity. The participants also reported what types of evidence they wanted and in what detail (e.g., subgroups, different outcomes). Users particularly wanted to see intervention effectiveness and quality, and policymakers also wanted to know the financial costs and negative consequences. Comprehension and preferences were remarkably consistent between the two samples. Groups communicating evidence about policy options can use these results to design summaries, toolkits and reports for expert and non-expert audiences.

Personal data increasingly serve as inputs to public goods. Like other types of contributions to public goods, personal data are likely to be underprovided. We investigate whether classical remedies to underprovision are also applicable to personal data and whether the privacy-sensitive nature of personal data must be additionally accounted for. In a randomized field experiment on a public online education platform, we prompt users to complete their profiles with personal information. Compared to a control message, we find that making public benefits salient increases the number of personal data contributions significantly. This effect is even stronger when additionally emphasizing privacy protection, especially for sensitive information. Our results further suggest that emphasis on both public benefits and privacy protection attracts personal data from a more diverse set of contributors.

We present a series of studies documenting what we call a ‘thick skin bias’ in people's perceptions of those living in poverty. Across a wide range of life events, from major to minor, people of lower socioeconomic status (SES) are systematically perceived as being less harmed by negative experiences than higher-SES people, even when this is patently false. In 18 studies, including a pre-registered survey of a nationally representative sample, we find that laypeople and professionals show the thick skin bias. We distinguish the bias from a tendency to dehumanize those in poverty and argue it cannot be attributed to the belief that the mere expectation that bad things will happen buffers people in poverty from suffering. The thick skin bias has potentially profound implications for the institutional and interpersonal neglect of those most in need of greater care and resources.

A growing body of evidence shows that politicians use motivated reasoning to fit evidence with prior beliefs. In this, they are not unlike other people. We use survey experiments to reaffirm prior work showing that politicians, like the public they represent, engage in motivated reasoning. However, we also show that politicians are more resistant to debiasing interventions than others. When required to justify their evaluations, politicians rely more on prior political attitudes and less on policy information, increasing the probability of erroneous decisions. The results raise the troubling implication that the specialized role of elected officials makes them more immune to the correction of biases, and in this way less representative of the voters they serve when they process policy information.

Financial incentives are often designed to benefit from behavioral insights. Individuals’ preferences for such behaviorally inspired incentives are rarely studied, nor is the role played by the behavioral insights that motivated them. This study aimed to let individuals design their own incentives (i.e., tailored incentives) and to explore which individual characteristics are associated with these preferences for tailored incentives. A sample of students (n = 182) tailored hypothetical incentives for visiting the gym. Incentives could be tailored by: (1) committing personal funds; (2) picking weekly payouts (increasing or decreasing); and (3) introducing payout risk while increasing value. Afterwards, (inter alia) loss aversion, probability weighting, time discounting, present bias, cognitive reflection and trait self-control were measured. A large majority indicated being willing to deposit their own money, and only very few individuals selected risky incentives. These heterogeneous preferences for financial incentives are poorly predicted by the individual characteristics measured (i.e., economic preferences and psychological traits). These results suggest that preferences for tailored incentives could be studied as input for the design of financial incentives. However, it is unclear whether tailoring incentives improves cost-effectiveness, as the lack of association between tailored incentives and the behavioral insights that motivate them has multiple conflicting interpretations.

Nudge plus is a modification of the toolkit of behavioral public policy. It incorporates an element of reflection – the plus – into the delivery of a nudge, either blended in or made proximate. Nudge plus builds on recent work combining heuristics and deliberation. It may be used to design prosocial interventions that help preserve the autonomy of the agent. The argument turns on seminal work on dual systems, which presents a subtler relationship between fast and slow thinking than commonly assumed in the classic literature in behavioral public policy. We review classic and recent work on dual processes to show that a hybrid is more plausible than the default-interventionist or parallel-competitive framework. We define nudge plus, set out what reflection could entail, provide examples, outline causal mechanisms, and draw testable implications.

As US college costs continue to rise, governments and institutions have quadrupled financial aid. Yet, the administrative process of receiving financial aid remains complex, raising costs for families and deterring students from enrolling. In two large-scale field experiments (N = 265,570), we test the impact of nudging high-school seniors in California to register for state scholarships. We find that simplifying communication and affirming belonging each significantly increase registrations, by 9% and 11%, respectively. Yet, these nudges do not impact the final step of the financial aid process – receiving the scholarship. In contrast, a simplified letter that affirms belonging while also making comparable cost calculations more salient significantly impacts college choice, increasing enrollment in the lowest net cost option by 10.4%. Our findings suggest that different nudges are likely to address different types of administrative burdens, and their combination may be the most effective way to shift educational outcomes.

Do policymaker perceptions reflect actual citizen needs? A vast literature has explored the extent to which policy is responsive to public opinion, but there is little systematic work on policymaker perceptions of social problems. We quantify social problems with a unique dataset of the number of phone calls placed by citizens to a free service that connects Michigan residents to service providers. We combine these data with a survey of local policymakers’ perceptions of social problems facing their own city shows, consistent with theories of bounded rationality, that policymakers use heuristics to make judgments about the extent of constituent needs in their city, and that policymaker perceptions reflect the prevalence of needs. However, partisan perceptions of needs diverge, with Democrats consistently perceiving greater needs than Republicans. There is no evidence that policy activity on the needs in the sample is responsive to constituent needs. We conclude with implications for theories of policy making and avenues for future research.

Criticisms of nudging suggest that nudges infringe on decision makers’ autonomy. Yet, little empirical research has explored whether people who are subjected to nudges agree. In three between-group experiments (N = 2083), we subject participants to contrasting choice architectures and measure experiences of autonomy, choice-satisfaction, perceived threat to freedom of choice, and objection to the choice architecture. Participants who received a prosocial opt-out default nudge made more prosocial choices but did not report lower autonomy or choice satisfaction than participants in opt-in default or active-choice conditions. This was the case even when the presence of the nudge was disclosed, and when monetary choice stakes were introduced. With monetary choice stakes, participants perceived the threat to freedom of choice as slightly higher in the nudge condition than in the other conditions, but objection to the choice architecture did not differ between the conditions. Taken together, our results suggest that default nudges are less manipulative and autonomy-infringing than sometimes feared. We recommend that policymakers include measures of choice experiences when testing out new interventions.

When governments and healthcare providers offer people cash rewards for weight loss, an assumption is that cash rewards are versatile, working equally well for everyone – for example, for all genders. No research to date has tested for gender difference in response to financial incentives for weight loss. We show in an randomized controlled trial (RCT) (n = 472) that cash incentives for weight loss only worked for males. The RCT consisted of a 3-month, self-administered online weight loss program. Offering a US$150 incentive for a 5% weight loss more than tripled the proportion of males who were successful, compared with a no-incentive Control arm (20.9% vs. 5.9%). On average, males in the incentive arm lost 2.4% of weight over 3 months, compared with 0.9% in the Control arm. The same incentive had no such effect on females: The average weight loss in the incentive arm was not significantly different than in the Control (1.03% and 1.44%, respectively), nor was the proportion of participants meeting the 5% weight loss goal (8.6% and 8.7%, respectively). This study shows that males respond better than females to financial incentives for weight loss.

Both theory on motivational crowding and recent empirical evidence suggest that nudging may sometimes backfire and actually crowd out prosocial behavior, due to decreased intrinsic motivation and warm glow. In this study, we tested this claim by investigating the effects of three types of nudges (default nudge, social norm nudge, and moral nudge) on donations to charity in a preregistered online experiment (N = 1098). Furthermore, we manipulated the transparency of the nudges across conditions by explicitly informing subjects of the nudges that were used. Our results show no indication that nudges crowd out prosocial behavior; instead, all three nudges increased donations. The positive effects of the nudges were driven by the subjects who did not perceive the nudges as attempts to manipulate their behavior, while donations among subjects who felt that the nudges were manipulative remained unaffected. Subjects’ self-reported happiness with their choice also remained unaffected. Thus, we find no indication that nudges crowded out warm glow when acting altruistically. Generally, our results are good news for the proponents of nudges in public policy, since they suggest that concerns about unintended motivational crowding effects on prosocial behavior have been overstated.

Behavioural science has been effectively used by policy makers in various domains, from health to savings. However, interventions that behavioural scientists typically employ to change behaviour have been at the centre of an ethical debate, given that they include elements of paternalism that have implications for people's freedom of choice. In the present article, we argue that this ethical debate could be resolved in the future through implementation and advancement of new technologies. We propose that several technologies which are currently available and are rapidly evolving (i.e., virtual and augmented reality, social robotics, gamification, self-quantification, and behavioural informatics) have a potential to be integrated with various behavioural interventions in a non-paternalistic way. More specifically, people would decide themselves which behaviours they want to change and select the technologies they want to use for this purpose, and the role of policy makers would be to develop transparent behavioural interventions for these technologies. In that sense, behavioural science would move from libertarian paternalism to liberalism, given that people would freely choose how they want to change, and policy makers would create technological interventions that make this change possible.

The Internet is gaining relevance as a platform where extremist organizations seek to recruit new members. For this preregistered study, we developed and tested a novel online game, Radicalise, which aims to combat the effectiveness of online recruitment strategies used by extremist organizations, based on the principles of active psychological inoculation. The game “inoculates” players by exposing them to severely weakened doses of the key techniques and methods used to recruit and radicalize individuals via social media platforms: identifying vulnerable individuals, gaining their trust, isolating them from their community and pressuring them into committing a criminal act in the name of the extremist organization. To test the game's effectiveness, we conducted a preregistered 2 × 2 mixed (pre–post) randomized controlled experiment (n = 291) with two outcome measures. The first measured participants’ ability and confidence in assessing the manipulativeness of fictitious WhatsApp messages making use of an extremist manipulation technique before and after playing. The second measured participants’ ability to identify what factors make an individual vulnerable to extremist recruitment using 10 profile vignettes, also before and after playing. We find that playing Radicalise significantly improves participants’ ability and confidence in spotting manipulative messages and the characteristics associated with vulnerability.

Behavioral scientists have begun to research ‘sludge,’ excessive frictions that make it harder for people to do what they want to do. Friction is also an important concept in transaction-cost economics. Nevertheless, sludge has been discussed without explicit referral to transaction costs. Several questions arise from this observation. Is the analogy to friction used differently in both literatures? If so, what are the key differences? If not, should we develop the concept of sludge when the well-established literature on transaction costs already exists? This conceptual article shows that sludge and transaction costs are related, but distinct, concepts, and that the literature on sludge can benefit from incorporating elements from transaction-cost research. For example, we suggest defining sludge as aspects of the choice architecture that lead to the experience of costs, organize sludges using a typology inspired by the transaction-cost literature, highlight specificity, uncertainty, and frequency as important determinants of the ‘sludginess’ of choice architecture, and show that sludge audits can be conducted using methods developed in the transaction-cost literature.

Although there has been a proliferation of research and policy work into how nudges shape people's behaviour, most studies stop far short of consumer welfare analysis. In the current work, we critically reflect on recent efforts to provide insights into the consumer welfare impact of nudges using willingness to pay and subjective well-being reports and explore an unobtrusive approach that can speak to the immediate emotional impacts of a nudge: automatic facial expression coding. In an exploratory lab study, we use facial expression coding to assess the short-run emotional impact of being presented with calorie information about a popcorn snack in the context of a stylised ‘Cinema experience’. The results of the study indicate that calorie information has heterogeneous impacts on people's likelihood of choosing the snack and on the emotions they experience during the moment of choice which varies based on their level of health-consciousness. The information does not, however, affect the emotions people go on to experience while viewing movie clips, suggesting that the emotional effects of the information are short-lived. We conclude by emphasising the potential of automatic facial expression coding to provide new insights into the immediate emotional impacts of nudges and calling for further research into this promising technique.