We report two studies investigating whether, and if so how, different low-cost interventions affect voter registration rates. Low-cost message-based interventions are increasingly used to promote target behaviours. While growing evidence shows that such ‘nudges’ often significantly impact behaviour, understanding of why interventions work or fail in particular contexts remains underdeveloped. In a natural field experiment conducted before the 2015 UK general election, we varied messages on a postcard sent by Oxford City Council to unregistered students encouraging them to join the electoral register. Our primary finding from the field study is that just one of our interventions – a reminder that people failing to register may be fined – has a significant positive impact. Offering small monetary rewards to register instead has a negative but insignificant effect. In a second study, using an online experiment we identify a particular mechanism explaining the influence of this intervention. Specifically, we show that our interventions have divergent effects on perceptions of the normative appropriateness of registering: emphasising that failing to register is punishable by law strengthened the perception that one ought to register, while offering monetary inducements for registering weakened the perception that doing so is an action already expected within society.

People's risk estimates often do not align with the evidence available to them. In particular, people tend to discount bad news (such as evidence suggesting their risk of being involved in a car accident is higher than they thought) as compared to good news (evidence suggesting it is lower) – this is known as the belief update bias. It has been assumed that individuals use motivated reasoning to rationalise away unwanted evidence (e.g., “I am a safe driver, thus these statistics do not apply to me”). However, whether reasoning is required to discount bad news has not been tested directly. Here, we restrict cognitive resources using a cognitive load (Experiment 1) and a time restriction manipulation (Experiment 3) and find that while these manipulations diminish learning in general, they do not diminish the bias. Furthermore, we also show that the relative neglect of bad news happens the moment new evidence is presented, not when participants are subsequently prompted to state their belief (Experiment 2). Our findings suggest that reasoning is not required for bad news to be discounted as compared to good news.

Millions of Europeans use online platforms with almost blind trust that the platforms operate in the interests of the consumer. However, the presentation of search results, transparency about contractual parties and the publication of user reviews that contribute to the value of online platforms in Europe's Single Digital Market also pose significant risks regarding consumer protection and market competition. The current study investigates how enhanced information transparency in online platforms might affect consumers’ trust in online activities and choice behaviour. Following an exploratory qualitative study, three online discrete-choice experiments were conducted with representative samples of 1200 respondents in each of four countries: Germany, Poland, Spain and the UK. The objective of the experiments was to test whether increased transparency in the presentation of online search information, details of contractual entities and the implications for consumer protection and user reviews and ratings would affect consumers’ choices. The results show that increased online transparency increases the probability of product selection. A comparison across the four countries found that the similarities in responses to online transparency were far greater than the differences. The findings are discussed in relation to the biases and heuristics identified in behavioural science. In conclusion, recommendations are made to increase online transparency, which the empirical evidence of this study shows would benefit both users and platform operators.

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.

We conducted two Facebook experiments (the first one during July 21–25, 2016, and the second during April 22–25, 2018) to determine what type of message related to injunctive norms is more effective in getting Hispanic women interested in learning about financial planning for retirement. We also explore how social media tools could be used in future interventions to promote retirement saving among Hispanic women. In both experiments, we found that a message centered on peer influence may be more successful than a message centered on familism in getting Hispanic women interested in learning more about financial planning for retirement. When we disaggregate our data by age and state, we find that click-through rates were higher among Hispanic women between 45 and 55 years old, and the largest numbers of impressions were among Hispanic women in California and Texas. When we disaggregate our data by device, we find that most study participants were reached through an Android smartphone.

A behavioural public policy movement has flourished within the global policy realm. While this movement has been deemed interdisciplinary, incorporating behavioural science theories and methods in a neoclassical economics-governed policy process, this paper analyses the bounded form of interdisciplinarity that characterizes it. We claim that an engagement is missing with the broader sweep of social sciences, which share similar concerns but deploy different analytical perspectives from those of behavioural public policy. Focusing on two central concepts (context and evidence), we aim to show how behavioural public policy's bounded interdisciplinarity implies constrained understandings of context and evidence, thereby limiting its complex problem-solving abilities. At the same time, we highlight some alternative examples of behavioural public policy practice that do explore new critical interdisciplinary horizons.

Public policies often involve “norm nudging”, the use of norm information to steer individual behavior in a prosocial direction. Analysis of social norm messaging often concentrates on the outcome measure: the potential change in behavior. The cognitive and psychological processes that underlie individuals’ response to norm information, especially the inferences they draw, are usually overlooked. This knowledge gap may lead to adverse consequences, such as messages backfiring. To (factually) justify norm nudging interventions, it is essential that policymakers understand the complex mechanisms that link context, social expectations and preferences, and how the interpretation of different types of messages affects behavior.

Neuroimaging methods provide insight into the neural mechanisms underlying the decision process, characterizing choice at the individual level and, in a growing number of contexts, predicting national- and market-level behavior. This dual capacity to examine heterogeneity while forecasting aggregate choice is particularly beneficial to those studying environmental decision-making. To effectively reduce residential energy usage and foster other pro-environmental behaviors, policy-makers must understand the effects of information frames and behavioral nudges across individuals who hold a diverse array of attitudes toward the environment and face a broad range of barriers to action. This paper articulates the potential of neuroeconomic methods to aid environmental policy-makers interested in behavior change, especially those interested in closing the energy efficiency gap. Investigation into the roles of affect, eco-labeling and social norms will be discussed, as well as personal identity and climate change beliefs. Combining neuroimaging with behavioral economics experiments can inform the development of effective messaging, characterize the influence of individual differences on the decision process and aid in forecasting the efficacy of policy interventions at scale.

The Behavioural Insights Team (BIT) has led in the promotion and adoption of behavioural science research in public policy. This comment addresses a number of issues that must be faced by BIT and the wider behavioural public policy agenda as the field becomes institutionalised and normalised within public policy internationally, in particular issues of ethics and professional codes.

How can we stimulate policymakers to make strategic decisions that enhance public service performance? Traditional strategy theories have not enabled us to answer this question. These theories focus on strategy processes or content in public organizations and networks and directly link these to public service performance. This article defines and elaborates on a conceptual framework that uses theory from behavioral science to unravel how policymakers can make strategic decisions that actually enhance the performance of public organizations and networks. This conceptual framework is labeled ‘behavioral public strategy’ and conceptualizes public strategy as a social process shaped by the individuals, teams and tools underlying it. Behavioral public strategy thus focuses on the micro-foundations of public strategy and how these micro-foundations influence strategic decisions. Moreover, behavioral public strategy links meso- and micro-levels by proposing a bathtub model where the relationship between public strategy and public service performance at the organizational and network levels is explained by the relationship between the micro-foundations of public strategy and the ensuing strategic decisions at the individual and team levels. This article connects three research streams that have been like ‘ships that pass in the night’, namely public strategy, behavioral public policy and behavioral public administration.

On the one hand, default nudges are proven to strongly influence behavior. On the other hand, a number of consumer autonomy and welfare concerns have been raised that hinder public policy applications. Both nudge success and ethical concerns depend heavily on the design of defaults. We identify six taxonomic characteristics that matter to the ethical and the nudge success dimension. We review the default nudge literature (N = 61) and review ethical studies to assess both dimensions concerning the taxonomy. When designing a default, a choice architect inevitably makes a decision concerning the characteristics. Among others, the results show three main findings. (1) The initial choice architecture regularly imposes welfare losses and impedes consumer autonomy. Forced active choosing can mitigate both issues. (2) Empirical evidence suggests that transparent defaults are similarly effective as the non-transparent counterparts. (3) The framing of the choice in combination with a choice structuring default leads to greater nudge success and tends to involve the reflective decision-making patterns. Choice architects can trade-off nudge success for legitimacy but a design change may also benefit one without harming the other. We discuss further options of choice architects to legitimize a default.

Recent surveys in China, South Korea, Brazil, South Africa, Russia, Australia, Italy, the UK, Canada, France, Germany, the USA, Japan, Hungary, and Denmark indicate that citizens generally are positive toward state nudging. However, less is known about differences in the support for nudging across socio-demographics and political party preferences, a research gap recently identified in the literature. This article investigates the relationship between the support for nudging and trust in public institutions through a population-representative survey in Sweden. It also analyzes differences in the support for nudging across political party preferences in two ideological dimensions: the economic left-right and cultural GAL-TAN spectra. Data were collected in December 2017 through a custom web survey, using Reisch and Sunstein's (2016) questionnaire. The respondents (N = 1032) were representative of the adult population with regard to gender, age, education, job sector, household income, living region, and political party preference. Sweden was found to belong to the cautiously pronudge nations (along with Japan, Hungary, and Denmark), contrary to hypotheses in previous research. Differences in the support for nudging were found along the economic left-right and GAL-TAN spectra. Individual nudges’ variation in support, polarization, and politicization are analyzed and discussed.

Prior research in the behavioral sciences has demonstrated that reminders can be an effective tool for encouraging health-related behavior changes. This article extends that literature by reporting the outcome of a randomized controlled trial of mailed vaccination reminders. In addition to making a substantive contribution regarding the efficacy of mailed reminders, this article also makes a methodological contribution: it illustrates how researchers can study the causal impact of an intervention even when a pure parallel trial is not possible. In this study, the Louisiana Department of Health sent postcard reminders regarding four recommended vaccinations (influenza, tetanus, shingles and pneumonia) to 208,867 senior residents of Louisiana. We used block randomization and a stepped wedge design to assess the efficacy of the intervention. Individuals were blocked by their prior vaccine record and randomized to receive the postcard in one of four consecutive months (October–January). The reminder postcard had an overall positive effect on vaccination rates. The statistically significant and substantively small increase in overall vaccination rates was driven by participants who received the postcard reminder early in the intervention period.

Once vaccines against COVID-19 became available in many countries, a new challenge has emerged – how to increase the number of people who vaccinate? Different policies are being considered and implemented, including behaviourally informed interventions (i.e., nudges). In this study, we have experimentally examined two types of nudges on representative samples of two countries – descriptive social norms (Israel) and saliency of either the death experience from COVID-19 or its symptoms (UK). To increase the legitimacy of nudges, we have also examined the effectiveness of transparent nudges, where the goal of the nudge and the reasons of its implementation (expected effectiveness) were disclosed. We did not find evidence that informing people that the vast majority of their country-people intend to vaccinate enhanced vaccination intentions in Israel. We also did not find evidence that making the death experience from COVID-19, or its hard symptoms, salient enhanced vaccination intentions in the UK. Finally, transparent nudges as well did not change the results. We further provide evidence for the reasons why people choose not to vaccinate, and whether different factors such as gender, belief in conspiracy theories, political ideology, and risk perception, play a role in people's intentions to vaccinate or susceptibility to nudges.

In October 2021, a majority of the UK gambling industry implemented a new UK safer gambling message, ‘take time to think’, which features on gambling advertising and websites. An effective safer gambling message could plausibly affect several relevant gambling behaviours, with previous research suggesting that message effectiveness is maximised via messages that are displayed prominently immediately prior to gambling. We experimentally tested this message's effect on four contemporaneous gambling behaviours (the proportion of available funds bet, clicks for help service information, the mean speed of play, and the total number of roulette spins made) in an incentivised online roulette game in a sample of UK-based online gamblers. Participants (n = 2,305) were randomly allocated to either (a) ‘no-message’ control, (b) ‘message’ shown throughout the condition or (c) a ‘message+’ condition, where the message was shown throughout and also via a popup immediately prior to the roulette game. Overall, the results showed no credible effects across the four outcome measures when comparing either of the message conditions to the no-message control. Even the prominent display of the ‘take time to think’ message did not lead to credible beneficial effects on a range of contemporaneous gambling behaviours.

By identifying well-being with preference satisfaction, mainstream normative economists were able to leave the determination of which specific things make people better or worse off to the individuals themselves. The findings of behavioral economics undermine the possibility of deferring in this way to individual preference. One response to this challenge to welfare economics is to distinguish the true preferences of individuals from their manifest preferences and to take true preferences to guide policy. In The Community of Advantage, Robert Sugden criticizes this strategy and proposes that economists appraise policies, institutions and outcomes by the opportunities they provide rather than by their contributions to welfare. This paper criticizes Sugden's view and argues for a modest solution that makes cautious use of preferences as indicators of well-being.

Behavioral policies are increasingly popular in a number of health care contexts. However, evidence of their effectiveness, specifically in low-income and highly disadvantaged populations, is limited. Some positive effects have been found for adaptive interventions, which merge more personalized approaches with advances in data collection and modern analytical methods. These approaches have only recently become feasible, as their implementation requires a confluence of large-scale datasets, contemporary machine learning, and validated behavioral insights. Such methods have considerable potential to improve outcomes without requiring substantial increases in effort on the part of individuals. Using examples from health insurance choice, clinical attendance rates, and prescription of medicines, we present an argument for how adaptive approaches, especially those considering disadvantaged populations explicitly, offer an opportunity to generate equity in public health.

In a ‘post-truth’ era in which personality and opinion trump evidence and reason, the need for frankness in debates about the use and boundaries of science and policy is high. We welcome the reflective and nuanced approach to behavioural science in policy-making in Sanders, Snijders and Hallsworth's (2018) piece. Despite our support for the approach in this paper, we suggest that there are deeper issues than are currently acknowledged. Our critique tackles three issues: the empirical, the normative and the political. In the first section, we examine what counts as ‘behavioural’ and how this label is used to legitimate a range of policy activities. We then look at randomised controlled trials in the next section, highlighting the extra-scientific dimensions of the empirical ‘What Works’ revolution. Finally, we question some ontological assumptions that drive empirical research and its translation into policy, asking where the collective is to be found in behavioural public policy.

Happiness economics as advocated by Frijters et al. makes three assumptions: that policy should be based on facts about the net effect of a factor on happiness; that wellbeing policy should be technocratic and centralized; and that the only credible objections come from critics who do not value happiness. We argue that all three should be rejected and that the science and policy of wellbeing should instead be pluralistic, context-sensitive and participatory.

Disclosure mandates are pervasive. Though designed to inform consumers, such mandates may lead consumers to draw false inferences – for example, that a product is harmful when it is not. When deciding to require disclosure of an ingredient in or characteristic of a product, regulators may be motivated by evidence that the ingredient or characteristic is harmful to consumers. But they may also be motivated by a belief that consumers have a right to know what they are buying or by interest-group pressure. Consumers who misperceive the regulator's true motive, or mix of motives, will draw false inferences from the mandated disclosure. If consumers think that the disclosure is motivated by evidence of harm, when in fact it is motivated by a belief in a right to know or by interest-group pressure, then they will be inefficiently deterred from purchasing the product. We analyze this general concern about disclosure mandates. We also offer survey evidence demonstrating that the risk of false inferences is serious and real.