Thursday, June 10, 2021

In contrast to previous research that used surveys, we found little evidence that mask wearers have strong preferences for caring for others and equality for all; it is more about social identity

Powdthavee N, Riyanto YE, Wong ECL, Yeo JXW, Chan QY (2021) When face masks signal social identity: Explaining the deep face-mask divide during the COVID-19 pandemic. PLoS ONE 16(6): e0253195, Jun 10 2021.

Abstract: With the COVID-19 pandemic still raging and the vaccination program still rolling out, there continues to be an immediate need for public health officials to better understand the mechanisms behind the deep and perpetual divide over face masks in America. Using a random sample of Americans (N = 615), following a pre-registered experimental design and analysis plan, we first demonstrated that mask wearers were not innately more cooperative as individuals than non-mask wearers in the Prisoners’ Dilemma (PD) game when information about their own and the other person’s mask usage was not salient. However, we found strong evidence of in-group favouritism among both mask and non-mask wearers when information about the other partner’s mask usage was known. Non-mask wearers were 23 percentage points less likely to cooperate than mask wearers when facing a mask-wearing partner, and 26 percentage points more likely to cooperate than mask wearers when facing a non-mask-wearing partner. Our analysis suggests social identity effects as the primary reason behind people’s decision whether to wear face masks during the pandemic.


In this paper, we conducted a pre-registered, online incentivized lab experiment using a high-powered sample of Americans to test whether people generally use others’ face mask usage as a signal of social identity instead of innate willingness to cooperate during the COVID-19 pandemic. In contrast to previous research that used surveys to demonstrate that mask wearers have strong preferences for caring for others and equality for all [9], we found little evidence that mask wearers behaved more cooperatively than non-mask wearers in the PD game compared to non-mask wearers when information about their own and the other person’s mask usage is not salient. However, more consistent with social identity theory, we found strong evidence of in-group versus out-group bias based on mask usage during the pandemic. Non-mask wearers were 23 percentage points (p = 0.001) less likely to cooperate than mask wearers when facing a mask-wearing partner, and 26 percentage points (p<0.001) more likely to cooperate than mask wearers when facing a non-mask wearing partner. These findings are surprising, considering that there is little evidence that mask wearers were generally more cooperative than non-mask wearers in the scenario where the information about mask usage was not known to the participants.

Our results are notably different from recent studies that found zero social identity effects associated with COVID-19 vaccination. Kohn et al. [34] demonstrated that vaccinators and non-vaccinators generally treat vaccinators better in prosocial activities and, in a follow-up study by Weisel [35], that there is little evidence of the politicization of vaccination in people’s prosocial behaviours even when, like face masks, there are more Democrats than Republicans who are pro-vaccine. One possible explanation for this is that, unlike face masks, vaccination and vaccination intentions are not readily visible to both in-group and out-group members. Hence, despite evidence of political partisanship based on vaccination against COVID-19 shown in Weisel [35], without visibility of one’s vaccination status to others, it would be less likely that vaccination is going to be affected by politicization when compared to wearing face masks in America [1014].

Moreover, not only have we demonstrated that face masks signal strong social identity, we have also uncovered evidence of an in-group bias based on face masks that is completely orthogonal to one’s political identity and remains unexplained in our regression model. Despite the politicization of face masks being the likely root cause of the social identity effects, our experimental evidence seems to suggest that people may have evolved over time to assign face mask usage as a minimal condition required for favouring in-group members and discriminating against out-group members.

Our results, which provide new insights into the extent and the mechanisms behind the deep divide over face masks in America, have important public health implications. With the more infectious strains, e.g., the UK (B.1.1.7) and South African (B.1.351) variants, taking over and vaccination programs still rolling in America, public messages designed to curb the transmission rate by increasing awareness about face mask effectiveness in protecting themselves and others in the community from COVID-19 [36] are unlikely to change non-mask wearers’ world views and behaviours towards mask usage as doing so would signal disloyalty to their held political identity. A better public health strategy might focus less on the details of the messages and more on the ‘messenger’ or the information source. Studies in behavioural economics have shown how messengers who are authority figures, share similar characteristics with and are likable to the target individuals, tend to be more successful in getting their messages across and, in turn, change individuals’ choices and behaviours [3738]. Given that part of the social-identity effects is explained by political identity, non-mask wearers might be more willing to listen to a message about face mask’s effectiveness from an authoritative figure in the Republican party or non-political figures who share similar characteristics or are generally well-liked by non-mask wearers. This could include, for example, family doctors of non-mask wearers and mask-wearing friends who share the same political affiliation as non-mask wearers. Future research could explore what type of messenger works best at reducing the social identity effects of face masks and, in-so-doing increase the mask usage rate in the United States and elsewhere around the world.

Finally, our findings, when viewed in conjunction with Korn et al. [34] and Wiesel [35], suggest that political partisanship based on health measures are more likely to lead to actual polarization in the take-up rate when the health measures in question are visible and salient to the individual and others in the community. Given the recent political discussions on vaccine passports [3940] and getting those who have been vaccinated against COVID-19 to wear a sticker visible to others [41], our results suggest that such efforts might lead to the unintended politicization of vaccinations, which would inevitably undermine the large-scale vaccination efforts to stop the spread of COVID-19.

Like all studies in social sciences, our study is not without limitations. One concern is the external validity of our findings. While it has been shown that people can easily identify PD games and play according to the game theory in the lab [42], it is possible that the same individuals may behave differently when facing a similar social dilemma in the real-world. It also remains to be seen whether our results can be generalised to other types of health measures such as vaccine passports and social distancing—scenarios where the stakes are large and interactions are repeated across countries and stages of the pandemic. Nonetheless, we have no reason to believe that the results depend on other characteristics of the subjects, materials, or context that are not already accounted for in the current study.

An Analysis was conducted on five Automated Vehicle Collisions, and consistent patterns emerged: The drivers were underloaded and did not effectively monitor the road environment, in part because of trust in automation

What can we learn from Automated Vehicle collisions? A deductive thematic analysis of five Automated Vehicle collisions. Siobhan E. Merriman et al. Safety Science, Volume 141, September 2021, 105320,


• A Deductive Thematic Analysis was conducted on five Automated Vehicle Collisions.

• Interconnection models were created, and consistent patterns emerged.

• Links were made with the drivers’ attitudes, mental models and trust in automation.

• The drivers were underloaded and did not effectively monitor the road environment.

• This impaired their ability to identify and avoid hazards in their path.

Abstract: There have been a number of high-profile collisions involving Automated Vehicles on the road. Although car manufacturers are making considerable investments into the development of Automated Vehicles, these collisions may deter the public from purchasing and using them. Therefore, solutions need to be developed to prevent these collisions from occurring in the future. One such solution is driver training. A previous literature review identified nine themes which are essential in Automated Vehicle driver training. In this article, a deductive thematic analysis was conducted on five high-profile Automated Vehicle collisions in order to demonstrate the relevance of these themes and to gain insights into how the driver’s behaviour contributed to each collision, thus understand the potential role of training in reducing collisions of this nature. By creating interconnection models for each collision, a consistent pattern emerged. A link was made with the drivers’ attitudes, the accuracy of their mental models and their level of trust in the automation. The automation caused the drivers to become underloaded, which impaired their ability to effectively monitor the automation and the road environment. This could have impaired their situation awareness and their ability to identify and avoid hazards in the path of their vehicle. This analysis suggests that future Automated Vehicle driver training programmes should be multifaceted and cover all nine themes. This analysis has validated these nine driver training themes, so these themes and interconnections can help in the development of a comprehensive training programme for drivers of Automated Vehicles in the future.

Keywords: Automated VehiclesSafetyDriver TrainingDeductive Thematic AnalysisAccident Analysis

Polarization: We see members of groups across the aisle as being our opposites on non-political dimensions & reflect personal preferences rather than empirical grop differences (preference for cats or dogs, or liking the color yellow)

When Polarization Triggers Out-Group “Counter-Projection” Across the Political Divide. Kathryn R. Denning, Sara D. Hodges. Personality and Social Psychology Bulletin, June 10, 2021.

Abstract: Although projecting one’s own characteristics onto another person is pervasive, “counter-projection,” or seeing the opposite of oneself in others is also sometimes found, with implications for intergroup conflict. After a focused review of previous studies finding counter-projection (often unexpectedly), we map conditions for counter-projection to an individual out-group member. Counter-projection requires identified antagonistic groups, is moderated by in-group identity, and is moderated by which information is assessed in the target person. Using political groups defined by support for former U.S. President Trump, across our Initial Experiment (N = 725) and Confirmatory Experiment (N = 618), we found counter-projection to individual political out-group targets for moral beliefs, personality traits, and everyday likes (e.g., preference for dogs vs. cats). Counter-projection was increased by in-group identification and overlapped considerably with “oppositional” out-group stereotypes, but we also found counter-projection independent of out-group stereotypes (degree of overlap with stereotyping depended on the information being projected).

Keywords: projection, politics, intergroup relations, polarization, stereotyping

In contrast to that intuitive view, this study argues that democratic rule and high state capacity combined produce higher levels of income inequality over time

Inclusive institutions, unequal outcomes: Democracy, state capacity, and income inequality. Mart Trasberg, Hector Bahamonde. European Journal of Political Economy, June 8 2021, 102048.


• Democratic rule combined with high state capacity produces higher income inequality.

• Mechanisms: foreign direct investment and financial development.

• We use a novel measure of state capacity based on cumulative census administration.

• Fixed effects panel regressions with the data from 126 countries between 1970 and 2013.

Abstract: Although the relationship between democratic rule and income inequality has received important attention in recent literature, the evidence has been far from conclusive. In this paper, we explore whether the redistributive effect of democratic rule is conditional on state capacity. Previous literature has outlined that pre-existing state capacity may be necessary for inequality-reducing policies under democratic rule. In contrast to that intuitive view, this study argues that democratic rule and high state capacity combined produce higher levels of income inequality over time. This relationship operates through the positive effect of high-capacity democratic context on foreign direct investment and financial development. By making use of a novel measure of state capacity based on cumulative census administration, we find empirical support for these claims using fixed-effects panel regressions with the data from 126 industrial and developing countries between 1970 and 2013.

Keywords: Income inequalityDemocracyState capacityFinancial DevelopmentFDI

Humor mistakes are more damaging for men than women: Women (vs men) who falter are still seen as more attentive, causing their mistakes to seem less substantial and bolstering downstream evaluations of them

No laughing matter: Why humor mistakes are more damaging for men than women. Taly Reich etl al. Journal of Experimental Social Psychology, Volume 96, September 2021, 104169.

Abstract: People of all genders regularly pursue both personal and professional objectives. To the latter, research has documented substantial barriers for women, especially when they make mistakes. As articulated by role congruity theory, their stereotypically communal nature appears at odds with the agentic objectives frequently seen as inherent to the workplace. To the former, though, how are women (versus men) evaluated in pursuit of communal objectives? We propose that observers are more likely to see men (versus women) as less successful after mistakes in the interpersonal realm. Nine preregistered experiments (N = 5400) test this proposition by targeting, specifically, the use of humor. They provide evidence for a process model by which women (versus men) who falter are still seen as more attentive, causing their mistakes to seem less substantial and bolstering downstream evaluations of them. Implications for gender, humor, and mistakes are discussed.

Keywords: GenderMistakeHumorPerson perceptionStereotypeRole congruity theory

New social interaction mechanisms—change in the rules of exchange and collective-action dilemmas—devised by the interacting individuals, allow for self-interested individuals to remain prosocial as societies grow

Cooperation in large-scale human societies—What, if anything, makes it unique, and how did it evolve? Simon T. Powers, Carel P. van Schaik, Laurent Lehmann. Evolutionary Anthropology: Issues, News, and Reviews, June 4 2021,

Abstract: To resolve the major controversy about why prosocial behaviors persist in large-scale human societies, we propose that two questions need to be answered. First, how do social interactions in small-scale and large-scale societies differ? By reviewing the exchange and collective-action dilemmas in both small-scale and large-scale societies, we show they are not different. Second, are individual decision-making mechanisms driven by self-interest? We extract from the literature three types of individual decision-making mechanism, which differ in their social influence and sensitivity to self-interest, to conclude that humans interacting with non-relatives are largely driven by self-interest. We then ask: what was the key mechanism that allowed prosocial behaviors to continue as societies grew? We show the key role played by new social interaction mechanisms—change in the rules of exchange and collective-action dilemmas—devised by the interacting individuals, which allow for self-interested individuals to remain prosocial as societies grow.


As discussed in Section 2, large-scale societies are dependent on prosocial behaviors for their existence. Yet, evolutionary theory shows that, everything else being equal, the selection pressures favoring prosocial behaviors decrease drastically as the number of interacting individuals increases, and hence prosocial behavior is unlikely to be favored in large groups (Powers & Lehmann, 2017). So what was the key mechanism that allowed for prosocial behavior to be sustained in the transition from small-scale to large-scale societies? Did prosocial behavior start to go against the actor's genetic self-interest as the scale of society increased? If so, it would need to be maintained by a decision-making mechanism that is less sensitive to material payoff compared to the decision-making mechanism of evolutionary biology (FMM) described in the previous section. Or alternatively, was prosocial behavior still payoff-sensitive because of changes in the social interaction mechanism?

4.1 Hypothesis 1: A special decision-making mechanism is the key driver of prosocial behavior in large-scale societies

The first hypothesis is the cultural group selection hypothesis (Richerson et al., 2016; Richerson & Boyd, 2005), which posits that the main driver maintaining the expression of prosocial behavior in the transition to large-scale societies is that humans are largely SLM agents with a high degree of prestige and conformity bias. These biases can maintain prosocial behavior within a group, even if the prosocial behavior is not payoff-sensitive and hence not an equilibrium behavior for self-interested agents. Prosocial acts in large-scale societies can therefore be altruistic under this hypothesis. If different groups reach different patterns of behavior, some with a greater frequency of prosocial behaviors, and some with less, then competition between groups can cause the prosocial behavior to spread throughout the population (Boyd et al., 2003; Henrich & Boyd, 2001). However, explicit formal models investigating these processes (Lehmann & Feldman, 2008; Molleman et al., 2013; Peña et al., 2009), and holding everything else constant in comparison to payoff-biased transmission, have so far generally failed to show that conformist-biased transmission favors the spread of prosocial behaviors. Prestige-biased transmission fares better, though (Molleman et al., 2013).

Cultural group selection was first proposed to explain the transition to large-scale social societies in economics (Hayek, 1988) but without much detail as to what form of competition between groups would do the job, a point that has been expressed as follows (Sugden, 1993):

Sometimes it seems to be suggested that less successful groups imitate more successful ones; sometimes, that individuals migrate from less successful to more successful groups; sometimes, that more successful groups reproduce more rapidly; and sometimes, that more successful groups exterminate less successful ones. I think we must assume that Hayek has no particular theory of group selection clearly in mind, but has the hunch that there is some common criterion of “success” or “fitness” that would be favored by any plausible theory.

Much the same variations of group competition have been proposed in the more recent literature (Richerson et al., 2016). It has been argued that cultural group selection will be reinforced if competition between groups involves the physical displacement of less prosocial groups by their more prosocial neighbors, for example, through warfare (Bowles et al., 2003; Boyd et al., 2003; Turchin et al., 2013). This type of group competition could cause payoff-insensitive prosocial behaviors to spread if SLMs use prestige or conformity bias, including altruistic behaviors. It has also been proposed that competition between groups could take the form of individuals either migrating to more successful groups, or imitating individuals in more successful groups (Richerson et al., 2016). This could cause payoff-insensitive prosocial behaviors to spread if SLMs use prestige bias when choosing the group to migrate to or imitate. In both of these cases, the social interaction mechanism does not matter much because of the agent's decision-making mechanism.

On the other hand, both types of group competition could also function with payoff-biased SLMs. However, in this case there would need to be a mechanism of social interaction which ensures that prosocial behaviors give a higher payoff than non-prosocial behaviors within a single group, for example, non-altruistic forms of sanctioning (Ostrom, 1990). And with payoff-biased SLMs, prosocial behaviors could only be cooperative in large groups of genetically unrelated individuals, and not altruistic. This idea has been proposed in some “weaker” versions of the cultural group selection hypothesis, which argue that prosocial behaviors in social dilemmas are actually cooperative equilibria within a single group (Richerson et al., 2016). However, this is typically an assumption of cultural group selection models (Bowles et al., 2003; Boyd & Richerson, 1990), rather than the models demonstrating the evolution of a social interaction mechanism that makes prosocial behaviors an equilibrium for self-interested individuals in a single group. In summary, there is no single theory of cultural group selection and the different variants make different assumptions on the payoff-sensitivity of individual behavior.

4.2 Hypothesis 2: A refinement of social interaction mechanisms is the key driver of prosocial behavior in large-scale societies

The second hypothesis is the institutional path hypothesis (Powers et al., 2016; Powers & Lehmann, 2017), which posits that the driver maintaining the expression of prosocial behavior in the transition to large-scale societies is a refinement of social interaction mechanisms (see Glossary, Table 1); namely, people changed the rules of their economic games. Individuals are thus assumed to have formal and/or informal political interactions that affect their economic interactions. The hypothesis is that as groups grew in size, individuals have refined and created new institutional rules supporting exchange and/or have changed systems of monitoring and sanctioning to handle larger numbers of individuals in collective-action problems. Institutional rules may also have reduced the effective number of individuals that interact through the creation of nested group structures (Ostrom, 1990). These new mechanisms of social interaction (not necessarily created by “deliberate design,” see more on this in the next section) would lead to prosocial behaviors increasing material payoff to the actor, and hence can be generally favored even by self-interested individuals. Prosociality among non-relatives in large-scale societies is thus always cooperative, rather than altruistic, and so individual behavior is always payoff-sensitive under this hypothesis.

Due to this payoff-sensitivity, the institutional-path hypothesis is compatible with RSM agents, behavioral ecology-biased FMM agents, and with SLM agents that use payoff-biased social learning when choosing prosocial behavior. It is also compatible with the PAM subtype of FMM to the extent that the institutional rules recreate the conditions where cooperative prosocial behaviors were payoff-sensitive in small-scale societies, for example, effective sharing of reputational information. Moreover, PAMs would be expected to create institutional rules similar to those found in small-scale societies in circumstances that are ecologically similar (Boyer & Petersen, 2012; Petersen et al., 2013), for example, to create rules of uniform sharing in periods of high resource variance (Cosmides & Tooby, 1992).

The form of the institutional rules a group ends up with will be influenced by proximate factors such as asymmetries in power, influence, and information (Singh et al., 2017), which determine the outcome of political interactions. Furthermore, only a subset of the individuals affected by the institutional rules may take part in the political interactions, and the interests of those taking part may not be representative of the interests of the group as a whole. Consequently, conflicts of interests between segments of the group may result in institutional rules not being optimal for all group members, as exemplified by the rise of highly despotic states such as Ancient Egypt, where despotic leaders biased institutional rules in favor of themselves. As such, the institutional path hypothesis is compatible with the widespread existence of inefficient institutions (North, 1990). On the other hand, when the interests of group members are aligned, or bargaining strengths are equal, then efficient institutions that increase average material-payoff are more likely to arise, a point that has been repeatedly stressed in the (political) economics literature (Greif, 2006; North, 1990; Ostrom, 1990).

The ability to create and enforce rules by self-interested individuals, especially over food sharing and property rights, would have been necessary to support the hunter-gatherer lifestyle (Hill, 2009). If hunter-gatherers did not have political interactions, then the institutional path hypothesis cannot explain the origin of large-scale societies. But there is evidence that hunter-gatherers do indeed have political interactions that affect their economic interactions, even though they lack the bureaucratic elements of large-scale societies. For example, when the extant Ache hunter-gatherer society transitioned from foraging to horticulture, they advocated and voted in local meetings to transfer fields from public to private ownership (Kaplan et al., 2005).

4.3 A combination of a special decision-making mechanism and a change in social interaction mechanisms?

Since both the cultural group selection and the institutional-path hypotheses assume a quantitative scaling up of the same kinds of exchange and collective-action problems, the above analysis shows that a key question in determining the driving factors in the transition to large-scale societies is what decision-making mechanism determines the expression of prosocial behavior. If individuals are sensitive to material payoff when choosing prosocial behavior, then there must have been a change in their social interaction mechanisms, as proposed by the institutional-path hypothesis. Without such a change, individuals should stop acting prosocially as they took part in exchanges and collective actions with more individuals, because when everything else is constant the pressures favoring prosocial behaviors decrease rapidly as the number of interacting individuals increases. Conversely, if there was no change in the social interaction mechanisms then individuals must be less sensitive to payoff. If so, a special decision-making mechanism must operate, whereby some form of cultural group selection does the work in explaining why prosocial behaviors, be they cooperative or altruistic, are stable in large-scale societies.

Because humans undoubtedly experiment with many behaviors by trial-and-error and do considerably rely on social learning (Legare, 2017), the rules constraining behavior in economic interactions to which a society converge must to some extent at least partly be the outcome of some “spontaneous order” (Hayek, 1988; Sugden, 1993; Vanberg, 1994) and not the outcome of fully deliberate design. A case in point is the advent of the usage of money, which is a typical rule-based change in economic organization that is both in the interest of individuals using it and that is likely to have spread gradually by payoff-biased social learning (Vanberg, 1994). As such, some ingredients of the cultural group selection hypothesis may be complementary with the institutional-path hypothesis, with competition between groups spreading different “spontaneous orders.” However, this depends critically on the exact version of “cultural group selection” that has been operating. If the version of cultural group selection involves altruistic behaviors or altruistic punishment, then it is not complementary as it assumes individuals that are not self-interested (André, 2011; Pinker, 2015).

Competition between groups resulting from warfare, differential migration, or environmentally induced extinctions acts as an equilibrium selection device (Binmore, 2005a; Boyd & Richerson, 1990; Harsanyi & Selton, 1988), favoring equilibria that lead to a higher average payoff for group members. Cultural group selection advocates traditionally stressed that high-payoff equilibria resulted from prestige and conformity biased SLMs causing behaviors to spread within groups even if they were not payoff-sensitive in the underlying social interaction mechanism, rather than being equilibria because they were payoff-sensitive (Henrich et al., 2015; Richerson & Boyd, 2005). But prosocial equilibria can also exist within groups under payoff-biased social learning, or under RSM agents that rationally choose their actions, if the right mechanisms of social interaction are in place. In this case, between-group competition can again act as an equilibrium selection device, spreading by cultural transmission mechanisms of interaction that lead to cooperation, without individuals acting against their self-interest (Binmore, 2005a; Boyd & Richerson, 1990; Harsanyi & Selton, 1988). This can act alongside the creation of mechanisms of interaction by bargaining and negotiation, helping to fill in where individuals are less than fully rational, that is, boundedly-rational RSMs or PAMs. On the other side, an explicit consideration of political interactions for changing institutional rules can complement cultural group selection models, which typically leave unspecified how a group arrives at a particular equilibrium in the first place. Much formal work remains to be done to ascertain the conditions under which such equilibrium selection processes at the level of rules of the game (instead of economic behavior under given rules) may work. There are essentially no models of this to date.

Despite ingredients of the cultural group selection and institutional path hypotheses not being necessarily mutually exclusive, there is a crucial need to understand whether the main driver of the evolution of prosocial behavior in large-scale societies is a special decision-making mechanism that can cause agents to perform prosocial behaviors that are not payoff-sensitive, or the creation of new mechanisms of social interaction that maintain the expression of payoff-sensitive behavior as group size increases. Without clarification, the perennial question of the extent to which prosocial behaviors in large-scale societies are compatible with (genetically) self-interested individuals will remain. Fully elucidating the evolved decision-making mechanism that humans use is extremely challenging. Determining, however, whether observed prosocial behaviors are payoff-sensitive is less challenging. For example, we can more easily determine whether systems of monitoring and sanctioning involve altruistic behaviors, or whether they directly benefit the individuals doing the monitoring and sanctioning by increasing their material payoff (Guala, 2012; Ostrom, 1990). If it is the former, then this suggests that a special decision-making mechanism was key to their spread and maintenance. If it is the latter, then the creation of new mechanisms of social interaction is likely to have been the key driver. Empirical work should thus pay more attention to the payoff sensitivity of monitoring and sanctioning behaviors.

We show how the degree to which consumers perceive a moral basis for their product attitudes robustly predicts their intended and actual marketplace behaviors

Morality Matters in the Marketplace: The Role of Moral Metacognition in Consumer Purchasing. Andrew Luttrell, Jacob D. Teeny and Richard E. Petty. Social Cognition, Volume 39 Issue 3, Jun 2021, online May 2021.

Abstract: To better understand the seemingly inconsistent influence of consumers' morality on their marketplace behaviors, we apply insights from research on attitude moralization to the consumer domain. That is, rather than predefining certain products as “moral,” this approach treats morality as the extent to which individual consumers metacognitively perceive their positive product attitudes as rooted in moral (vs. non-moral) considerations. Across multiple studies (N = 1,105), a wide variety of product categories, and multiple methodological approaches (i.e., correlational, experimental, and longitudinal), we show how the degree to which consumers perceive a moral basis for their product attitudes robustly predicts their intended and actual marketplace behaviors. Importantly, these findings hold above and beyond overall attitudes, other metacognitive assessments (e.g., certainty and ambivalence), and explicit product quality. By extending prior research in moral social cognition to the consumer domain, we provide a more refined account of morality's role in consumer behavior.

An effect of the mere presence of a phone on relationship quality & creativity is at minimum harder to find than what was previously assumed in the literature: This research contributes to qualify the view that smartphones are harmful

Linares C, Sellier A-L (2021) How bad is the mere presence of a phone? A replication of Przybylski and Weinstein (2013) and an extension to creativity. PLoS ONE 16(6): e0251451. Jun 9 2021.

Abstract: A 2013 article reported two experiments suggesting that the mere presence of a cellphone (vs. a notebook) can impair the relationship quality between strangers. The purpose of the present research is twofold: (1) closely replicate this article’s findings, and (2) examine whether there may be an impact of the mere presence of a phone on creativity, whether at a group- or an individual- level. In two experiments (N = 356 participants, 136 groups), we followed the original procedure in the 2013 article. In particular, groups of participants who had never seen each other before the study had a conversation in the mere presence of either a smartphone or a notebook. The participants then carried out creative tasks, in groups (Studies 1 and 2) or alone (Study 1). In both studies, we failed to replicate the original results on relationship quality. We also failed to find any effect of the mere presence of a phone on creativity. We discuss possible reasons which may have caused differences between our results and the original ones. Our main conclusion is an effect of the mere presence of a phone on relationship quality and creativity is at minimum harder to find than what was previously assumed in the literature. More generally, this research contributes to qualify the view that smartphones are harmful.

General discussion

In two studies, we failed to replicate Przybylski and Weinstein’s [12] results showing an adverse effect of the mere presence of a mobile phone on relationship formation, when considering both dyads and triads of strangers. We also did not find any effect of the mere presence of a mobile phone on any aspect of creative cognition, examining both divergent and convergent creativity processes and outputs, and both group and individual creativity. These results suggest that mere presence of a mobile phone may not be as harmful as has been previously claimed [1213].

Non-replication of Przybylski and Weinstein (2013)

The failed replication result directly adds to the line of research on the negative consequences of the mere presence of a mobile device [12134951], by suggesting that this negative influence may not be as marked as was previously assumed. If we cannot exclude that there might be other instances where this presence is harmful, our findings at least point out the fragility of the phenomenon. At a broader level, our results also nuance the dominant view that smartphones and technology are harmful, adding to burgeoning research that is casting doubt on the pervasiveness of their negative effects [e.g., 4877]. Our findings also complement research on mere exposure effects [7880]. Finally, our research supports the importance of replications [e.g., 298182]: Until an effect has been independently replicated, researchers need to remain cautious in assuming its existence [2831].

Despite our best efforts to conduct the closest replication as possible, our studies contain limitations. First, null effects do not invalidate an effect. It may be that the mere presence of the phone is harmful in different populations from those we sampled (e.g., in populations where the use of the smartphone may not be as pervasive as in large European cities). Second, even though our sample sizes were much greater than those in Przybylski and Weinstein [12], they may not have provided enough power to detect an effect [77]. Third, we measured relationship quality after the creative tasks and self-reports on the creative process, which might have wiped out the effect due to fatigue or contamination.

Is there a way to reconcile our results with those of Przybylski and Weinstein [12]? We see several possibilities, all of which relate to the timing of our experiments. We collected our data in 2018, compared to Przybylski and Weinstein (in or before 2012) [12]. The first possibility is that people might have simply gotten used to the presence of mobile devices, which could make them immune to their mere presence. Relatedly, our sample included mainly participants in their twenties, that belong to a generation who grew up with smartphones, and thus who might find their presence very natural. Another reason could be that the technology has evolved greatly between 2012 and 2018. Przybylski and Weinstein [12] used a cellphone, while we used a smartphone. Indeed, the number of smartphone users worldwide has more than doubled during this interval [83]. Additionally, people have developed strong bonds to them, although this is less likely to explain our results since in our studies, participants were exposed to a lab device [778485]. If any of these conjectures were true, then our findings would provide an updated assessment of the social consequences of the mere presence of a mobile phone, suggesting that its effect was short-lived.

Null effect on creativity

The absence of evidence supporting a link between the mere presence of a smartphone and creativity advances the exploration of the effects of technology on idea generation. Our results suggest that the mere presence of a technological device like a smartphone may not affect general measures of creativity, whether positively or negatively. Previous research has pointed out the critical role of the environment for creativity which can be affected by incidental cues like sound or background color or the presence of physical objects [668690]. Relatedly, a lay belief exists that a creative environment should be free from any distractions [9192]. Our findings suggest that creativity may not be that sensitive to the mere presence of technology.

One limitation of this investigation is that participants did the creativity tasks only after the conversation. However, in the real-world, creativity endeavors are rarely isolated from other processes, and we would argue that this improbably caused our null effects.

Implications and avenues for future research

The main implication of this research is to moderate calls to completely isolate from smartphones’ presence. It may not be necessary to ban even switched off smartphones from the dinner table or to enforce strict cellphone policies in organizations [9396]. For instance, the American, French and British governments have a no-phone policy during meetings, whereby each member has to leave their phones at the entry of the meeting room [97]. Our findings suggest that these constraints could be partly released, at least for meetings in which there is no concern that sensible information may be recorded.

Of course, when people’s own smartphones are present, the temptation to use them might still be detrimental for social interactions or creativity [199899]. In Misra et al. [13] for instance, acquaintances in the mere presence of their own mobile devices experienced a lower relationship quality, although similarly to Przybylski and Weinstein [12], this finding remains to be replicated. In a study we do not report here, we investigated whether individual idea generation could be affected by the presence of one’s own smartphone. Again, we observed no effect on creative cognition. At this point, it is our view that there is not much influence of the mere presence of a phone on creative cognition. What may be worthwhile investigating are ways in which smartphones may impact creativity, other than via their mere presence. For instance, future research could explore the difference between generating ideas on one’s smartphone rather than on one’s personal computer [8485]. This could also be interesting when exchanging ideas with other people, in the wake of research on electronic brainstorming [100102]. More broadly, the topic of creativity and technology still offers a wide field of investigation.


We did not replicate Przybylski and Weinstein’s [12] finding that the mere presence of a mobile device impairs relationship quality, nor did we find any effect of this presence on creativity. There is one practical recommendation arising from our results: next time you meet a stranger or work on a creative task, you may leave your phone on the table. Just turn on the airplane mode.

Many people listen to music for hours every day, often near bedtime; we investigated whether music listening affects sleep, focusing on a rarely explored mechanism: involuntary musical imagery (earworms)

Bedtime Music, Involuntary Musical Imagery, and Sleep. Michael K. Scullin, Chenlu Gao, Paul Fillmore. Psychological Science, June 9, 2021.

Abstract: Many people listen to music for hours every day, often near bedtime. We investigated whether music listening affects sleep, focusing on a rarely explored mechanism: involuntary musical imagery (earworms). In Study 1 (N = 199, mean age = 35.9 years), individuals who frequently listen to music reported persistent nighttime earworms, which were associated with worse sleep quality. In Study 2 (N = 50, mean age = 21.2 years), we randomly assigned each participant to listen to lyrical or instrumental-only versions of popular songs before bed in a laboratory, discovering that instrumental music increased the incidence of nighttime earworms and worsened polysomnography-measured sleep quality. In both studies, earworms were experienced during awakenings, suggesting that the sleeping brain continues to process musical melodies. Study 3 substantiated this possibility by showing a significant increase in frontal slow oscillation activity, a marker of sleep-dependent memory consolidation. Thus, some types of music can disrupt nighttime sleep by inducing long-lasting earworms that are perpetuated by spontaneous memory-reactivation processes.

Keywords: music cognition, stuck-song syndrome, involuntary memory, slow-wave activity, primary auditory cortex, open data, open materials