Megastudies improve the impact of applied behavioural science.

Policy-makers are increasingly turning to behavioural science for insights about how to improve citizens' decisions and outcomes1. Typically, different scientists test different intervention ideas in different samples using different outcomes over different time intervals2. The lack of comparability of such individual investigations limits their potential to inform policy. Here, to address this limitation and accelerate the pace of discovery, we introduce the megastudy-a massive field experiment in which the effects of many different interventions are compared in the same population on the same objectively measured outcome for the same duration. In a megastudy targeting physical exercise among 61,293 members of an American fitness chain, 30 scientists from 15 different US universities worked in small independent teams to design a total of 54 different four-week digital programmes (or interventions) encouraging exercise. We show that 45% of these interventions significantly increased weekly gym visits by 9% to 27%; the top-performing intervention offered microrewards for returning to the gym after a missed workout. Only 8% of interventions induced behaviour change that was significant and measurable after the four-week intervention. Conditioning on the 45% of interventions that increased exercise during the intervention, we detected carry-over effects that were proportionally similar to those measured in previous research3-6. Forecasts by impartial judges failed to predict which interventions would be most effective, underscoring the value of testing many ideas at once and, therefore, the potential for megastudies to improve the evidentiary value of behavioural science.

Poison Parasite Counter: Turning Duplicitous Mass Communications Into Self-Negating Memory-Retrieval Cues.

Disinformation in politics, advertising, and mass communications has proliferated in recent years. Few counterargumentation strategies have proven effective at undermining a deceptive message over time. This article introduces the Poison Parasite Counter (PPC), a cognitive-science-based strategy for durably countering deceptive communications. The PPC involves inserting a strong (poisonous) counter-message, just once, into a close replica of a deceptive rival's original communication. In parasitic fashion, the original communication then "hosts" the counter-message, which is recalled on each reexposure to the original communication. The strategy harnesses associative memory to turn the original communication into a retrieval cue for a negating counter-message. Seven experiments (N = 3,679 adults) show that the PPC lastingly undermines a duplicitous rival's original communication, influencing judgments of communicator honesty and favorability as well as real political donations.

Video-Based Approach to Engaging Parents into a Preventive Parenting Intervention for Divorcing Families: Results of a Randomized Controlled Trial.

The public health impact of evidence-based, preventive parenting interventions has been severely constrained by low rates of participation when interventions are delivered under natural conditions. It is critical that prevention scientists develop effective and feasible parent engagement methods. This study tested video-based methods for engaging parents into an evidence-based program for divorcing parents. Three alternative versions of a video were created to test the incremental effectiveness of different theory-based engagement strategies based on social influence and health behavior models. A randomized controlled trial was conducted to compare the three experimental videos versus two control conditions, an information-only brochure and an information-only video. Participants were attendees at brief, court-mandated parent information programs (PIPs) for divorcing or never married, litigating parents. Of the 1123 eligible parents, 61% were female and 13% were never married to the child's other parent. Randomization to one of five conditions was conducted at the PIP class level, blocking on facilitator. All participants completed a 15-item, empirically validated risk index and an invitation form. Results of regression analyses indicated that the most streamlined version, the core principles video, significantly increased parents' interest in participating in the parenting intervention, enrollment during a follow-up call, and initiation (i.e., attending at least one session) compared to one or the other control conditions. Findings suggest that videos based on social influence and health behavior theories could provide an effective and feasible method for increasing parent engagement, which would help maximize the public health benefits of evidence-based parenting interventions.

The uses (and abuses) of influence.

The ability to persuade others to contribute to your efforts is a key skill for managers, for team members--for anyone who wants to elevate the probability of success. Research by leading social scientist Robert Cialdini has found that persuasion works by appealing to certain deeply rooted human responses: liking, reciprocity, social proof, commitment and consistency, authority, and scarcity. In this edited interview with HBR's executive editor, Cialdini expands on the six principles of persuasion and how leaders can make effective, authentic use of them in everyday business situations. He also previews findings from new research on the ethics of influence and how dishonesty affects individuals and the organization.

Normative social influence is underdetected.

The present research investigated the persuasive impact and detectability of normative social influence. The first study surveyed 810 Californians about energy conservation and found that descriptive normative beliefs were more predictive of behavior than were other relevant beliefs, even though respondents rated such norms as least important in their conservation decisions. Study 2, a field experiment, showed that normative social influence produced the greatest change in behavior compared to information highlighting other reasons to conserve, even though respondents rated the normative information as least motivating. Results show that normative messages can be a powerful lever of persuasion but that their influence is underdetected.

The Constructive, Destructive, and Reconstructive Power of Social Norms: Reprise.

The influence of social norms on behavior has been a longstanding storyline within social psychology. Our 2007 Psychological Science publication presented a new rendition of this classic telling. The reported field experiment showed that social norms could be leveraged to promote residential energy conservation, but importantly, the descriptive norm was shown to increase consumption for low-consuming households. This potential destructive effect of social norms was eliminated with the addition of an injunctive message of social approval for using less energy. The article is among the 30 most-cited articles across all APS publications, which we attribute to our methodology, which measured real behavior in a large-scale field experiment and to several circumstances associated with the timing of the work. The article coincided with the explosion of social media, the emergence of behavioral economics, and a heightened level of concern about climate change. These contemporaneous activities set the stage for our work and for its high degree of citation.

The spyglass self: a model of vicarious self-perception.

Self-perception theory posits that people sometimes infer their own attributes by observing their freely chosen actions. The authors hypothesized that in addition, people sometimes infer their own attributes by observing the freely chosen actions of others with whom they feel a sense of merged identity--almost as if they had observed themselves performing the acts. Before observing an actor's behavior, participants were led to feel a sense of merged identity with the actor through perspective-taking instructions (Study 1) or through feedback indicating that their brainwave patterns overlapped substantially with those of the actor (Studies 2-4). As predicted, participants incorporated attributes relevant to an actor's behavior into their own self-concepts, but only when they were led to feel a sense of merged identity with the actor and only when the actor's behavior seemed freely chosen. These changes in relevant self-perceptions led participants to change their own behaviors accordingly. Implications of these vicarious self-perception processes for conformity, perspective-taking, and the long-term development of the self-concept are discussed.

Blatant benevolence and conspicuous consumption: when romantic motives elicit strategic costly signals.

Conspicuous displays of consumption and benevolence might serve as "costly signals" of desirable mate qualities. If so, they should vary strategically with manipulations of mating-related motives. The authors examined this possibility in 4 experiments. Inducing mating goals in men increased their willingness to spend on conspicuous luxuries but not on basic necessities. In women, mating goals boosted public--but not private--helping. Although mating motivation did not generally inspire helping in men, it did induce more helpfulness in contexts in which they could display heroism or dominance. Conversely, although mating motivation did not lead women to conspicuously consume, it did lead women to spend more publicly on helpful causes. Overall, romantic motives seem to produce highly strategic and sex-specific self-presentations best understood within a costly signaling framework.

Peacocks, Picasso, and parental investment: The effects of romantic motives on creativity.

Four experiments explored the effects of mating motivation on creativity. Even without other incentives to be creative, romantic motives enhanced creativity on subjective and objective measures. For men, any cue designed to activate a short-term or a long-term mating goal increased creative displays; however, women displayed more creativity only when primed to attract a high-quality long-term mate. These creative boosts were unrelated to increased effort on creative tasks or to changes in mood or arousal. Furthermore, results were unaffected by the application of monetary incentives for creativity. These findings align with the view that creative displays in both sexes may be linked to sexual selection, qualified by unique exigencies of human parental investment.

Going along versus going alone: when fundamental motives facilitate strategic (non)conformity.

Three experiments examined how 2 fundamental social motives--self-protection and mate attraction--influenced conformity. A self-protective goal increased conformity for both men and women. In contrast, the effects of a romantic goal depended on sex, causing women to conform more to others' preferences while engendering nonconformity in men. Men motivated to attract a mate were particularly likely to nonconform when (a) nonconformity made them unique (but not merely a member of a small minority) and when (b) the topic was subjective versus objective, meaning that nonconformists could not be revealed to be incorrect. These findings fit with a functional evolutionary model of motivation and behavior, and they indicate that fundamental motives such as self-protection and mate attraction can stimulate specific forms of conformity or nonconformity for strategic self-presentation.

Overcoming the self-promotion dilemma: interpersonal attraction and extra help as a consequence of who sings one's praises.

Prior research has shown that positive information presented by a third party shields people from the negative consequences of being perceived as self-promoting. But in many contexts, those third parties are intermediaries with a financial interest in the person being promoted rather than neutral parties. In three experimental studies, the authors demonstrate that even when intermediaries are not neutral, they can be helpful for overcoming the self-promotion dilemma--the need to assert one's competence but not be harmed by the fact that people who self-promote are viewed negatively. The authors find that hiring an agent to sing one's praises results in more favorable perceptions of the client, which contributes, in turn, to a greater willingness to offer that person assistance. It is also shown that even when the intermediary is physically present and seen to be complicit with the client, the positive effects of having someone else speak on one's behalf persist.

Dispelling the illusion of invulnerability: the motivations and mechanisms of resistance to persuasion.

Three studies examined the impact of a treatment designed to instill resistance to deceptive persuasive messages. Study 1 demonstrated that after the resistance treatment, ads using illegitimate authority-based appeals became less persuasive, and ads using legitimate appeals became more persuasive. In Study 2, this resistance generalized to novel exemplars, persevered over time, and appeared outside of the laboratory context. In Study 3, a procedure that dispelled participants' illusions of invulnerability to deceptive persuasion maximized resistance to such persuasion. Overall, the present studies demonstrate that attempts to confer resistance to appeals will likely be successful to the extent that they install 2 conceptual features: perceived undue manipulative intent of the source of the appeal and perceived personal vulnerability to such manipulation.

Bodies obliged and unbound: differentiated response tendencies for injunctive and descriptive social norms.

The authors suggest that injunctive and descriptive social norms engage different psychological response tendencies when made selectively salient. On the basis of suggestions derived from the focus theory of normative conduct and from consideration of the norms' functions in social life, the authors hypothesized that the 2 norms would be cognitively associated with different goals, would lead individuals to focus on different aspects of self, and would stimulate different levels of conflict over conformity decisions. Additionally, a unique role for effortful self-regulation was hypothesized for each type of norm-used as a means to resist conformity to descriptive norms but as a means to facilitate conformity for injunctive norms. Four experiments supported these hypotheses. Experiment 1 demonstrated differences in the norms' associations to the goals of making accurate/efficient decisions and gaining/maintaining social approval. Experiment 2 provided evidence that injunctive norms lead to a more interpersonally oriented form of self-awareness and to a greater feeling of conflict about conformity decisions than descriptive norms. In the final 2 experiments, conducted in the lab (Experiment 3) and in a naturalistic environment (Experiment 4), self-regulatory depletion decreased conformity to an injunctive norm (Experiments 3 and 4) and increased conformity to a descriptive norm (Experiment 4)-even though the norms advocated identical behaviors. By illustrating differentiated response tendencies for each type of social norm, this research provides new and converging support for the focus theory of normative conduct.

Storming the servers: a social psychological analysis of the First Internet War.

In April 2007, the First Internet War began. Owing to the relocation of a World War II-era Soviet war memorial in Estonia, angry protestors, primarily of Russian descent, engaged in a month-long series of coordinated online attacks on Estonia's Internet infrastructure that disabled it for several days. We analyze this real-world event from a social psychological perspective. Specifically, we review the details surrounding the event and examine why protest manifested in this form of online attack and discuss how it was successfully orchestrated from a framework provided by social psychology, the science of human social interaction. We argue that the psychological principles of loss, relative anonymity of online interaction, group membership and adherence to group norms, social validation, and contagion all contributed to the success of the attacks.

We Have to Break Up.

Three mostly positive developments in academic psychology-the cognitive revolution, the virtual requirement for multiple study reports in our top journals, and the prioritization of mediational evidence in our data-have had the unintended effect of making field research on naturally occurring behavior less suited to publication in the leading outlets of the discipline. Two regrettable consequences have ensued. The first is a reduction in the willingness of researchers, especially those young investigators confronting hiring and promotion issues, to undertake such field work. The second is a reduction in the clarity with which nonacademic audiences (e.g., citizens and legislators) can see the relevance of academic psychology to their lives and self-interest, which has contributed to a concomitant reduction in the availability of federal funds for basic behavioral science. Suggestions are offered for countering this problem.

Fear and Loving in Las Vegas: Evolution, Emotion, and Persuasion.

How do arousal-inducing contexts, such as frightening or romantic television programs, influence the effectiveness of basic persuasion heuristics? Different predictions are made by three theoretical models: A general arousal model predicts that arousal should increase effectiveness of heuristics; an affective valence model predicts that effectiveness should depend on whether the context elicits positive or negative affect; an evolutionary model predicts that persuasiveness should depend on both the specific emotion that is elicited and the content of the particular heuristic. Three experiments examined how fear-inducing versus romantic contexts influenced the effectiveness of two widely used heuristics-social proof (e.g., "most popular") and scarcity (e.g., "limited edition"). Results supported predictions from an evolutionary model, showing that fear can lead scarcity appeals to be counter-persuasive, and that romantic desire can lead social proof appeals to be counter-persuasive. The findings highlight how an evolutionary theoretical approach can lead to novel theoretical and practical marketing insights.

The constructive, destructive, and reconstructive power of social norms.

Despite a long tradition of effectiveness in laboratory tests, normative messages have had mixed success in changing behavior in field contexts, with some studies showing boomerang effects. To test a theoretical account of this inconsistency, we conducted a field experiment in which normative messages were used to promote household energy conservation. As predicted, a descriptive normative message detailing average neighborhood usage produced either desirable energy savings or the undesirable boomerang effect, depending on whether households were already consuming at a low or high rate. Also as predicted, adding an injunctive message (conveying social approval or disapproval) eliminated the boomerang effect. The results offer an explanation for the mixed success of persuasive appeals based on social norms and suggest how such appeals should be properly crafted.