Social Contagion Effects Research Articles

Happy house: Spousal weight and individual well-being

We use life satisfaction and Body Mass Index (BMI) information from three waves of the GSOEP to test for social interactions in BMI between spouses. Social interactions require that the cross-partial effect of partner's weight and own weight in the utility function be positive. Using life satisfaction as a utility proxy, semi-parametric regressions show that the correlation between satisfaction and own BMI is initially positive, but turns negative after some threshold. Critically, this latter threshold increases with partner's BMI when the individual is overweight. The negative well-being impact of own BMI is thus lower when the individual's partner is heavier, which is consistent with social contagion effects in weight. However, this relationship may also reflect selection on the marriage market or omitted variables, and it is difficult to think of convincing instruments that would allow causality to be clearly established.

The Social Contagion Effect of Marijuana Use among Adolescents

BackgroundResearch on adolescent substance use has consistently identified a strong relationship between adolescent behavior and the behavior of their peers. However, peer effects are difficult to estimate and causal interpretations must be undertaken with caution since individuals in most cases choose with whom to associate. In this paper we seek to empirically quantify the causal role of peer social networks in explaining marijuana usage among adolescents.Methods and FindingsUsing data from a nationally representative sample of adolescents we utilize a multivariate structural model with school-level fixed effects to account for the problems of contextual effects, correlated effects and peer selections to purge the potential biases from the estimates of peer influence. Our peer group measures are drawn not only from the nomination of close friends (N = 6,377), but also from classmates (N = 19,335). Marijuana usage among the peer groups were constructed using the peers' own report of their marijuana consumption. Controlling for parent level characteristics, and other demographic parameters, we find that a 10% increase in the proportion of close friends and classmates who use marijuana increases the probability that an individual chooses to use marijuana by 5%.ConclusionOur findings indicate that peer effects are important determinants of marijuana use even after controlling for potential biases We also found evidence to show that the influence of close friends and the more exogenous classmates are quite similar in magnitude under our preferred specification, supporting theory predicting the importance of peer influence. Effective policy aimed at reducing marijuana usage among adolescents would consider these significant peer effects.

Creating Social Contagion Through Viral Product Design: A Randomized Trial of Peer Influence in Networks

We examine how firms can create word-of-mouth peer influence and social contagion by designing viral features into their products and marketing campaigns. To econometrically identify the effectiveness of different viral features in creating social contagion, we designed and conducted a randomized field experiment involving the 1.4 million friends of 9,687 experimental users on Facebook.com. We find that viral features generate econometrically identifiable peer influence and social contagion effects. More surprisingly, we find that passive-broadcast viral features generate a 246% increase in peer influence and social contagion, whereas adding active-personalized viral features generate only an additional 98% increase. Although active-personalized viral messages are more effective in encouraging adoption per message and are correlated with more user engagement and sustained product use, passive-broadcast messaging is used more often, generating more total peer adoption in the network. Our work provides a model for how randomized trials can identify peer influence in social networks. This paper was accepted by Pradeep Chintagunta and Preyas Desai, special issue editors. This paper was accepted by Pradeep Chintagunta and Preyas Desai, special issue editors.

Social Contagion and Information Technology Diffusion: The Adoption of Electronic Medical Records in U.S. Hospitals

We use a social contagion lens to study the dynamic, temporal process of the diffusion of electronic medical records in the population of U.S. hospitals. Social contagion acknowledges the mutual influence among organizations within an institutional field and implicates information transmission through direct contact and observation as the mechanisms underlying influence transfer. We propose hypotheses predicting a hospital's likelihood of adopting electronic medical records as a function of its susceptibility to the influence of prior adopters, the infectiousness or potency of influence exerted by adopting hospitals, and its social and spatial proximity to prior adopters. Results obtained by fitting a heterogeneous diffusion model to data from a sample drawn from an annual survey, spanning 1975 to 2005, of almost 4,000 U.S. hospitals suggest that diffusion can be accelerated if specific attention is given to increasing social contagion effects. In particular, with respect to susceptibility to influence, greater hospital size and age are positively related to the likelihood of adoption for nonadopters, whereas younger hospitals are associated with greater infectiousness for adopters. A hospital's “celebrity” status also contributes to its infectiousness. We further find strong effects for social proximity and significant regional effects for spatial proximity and hospital size, suggesting that geographical covariates should be included in diffusion studies. Results also reinforce the importance of theorizing about and including interactions in examinations of social contagion.

Social contagion effects in experiential information exchange on bulletin board systems

This research indicates that the attraction in disseminating a certain topic is dependent on the experiential nature of information on bulletin board systems. Compared to cognitive posts, experiential posts demonstrate a contagion effect. That is, when in-and-between posts focus on experiential information at the early stage of communication, more experiential posts appear at the later stage of the discussion on the same topic. Additionally, the involvement of opinion leaders in positive posts also promotes the dissemination of experiential information. Implications of this research can be extended to design and improve the effectiveness and efficiency of online and offline word-of-mouth communication.

Creating Social Contagion Through Viral Product Design: A Randomized Trial of Peer Influence in Networks

We examine how firms can create word-of-mouth peer influence and social contagion by designing viral features into their products and marketing campaigns. Word-of-mouth (WOM) is generally considered to be more effective at promoting product contagion when it is personalized and active. Unfortunately, the relative effectiveness of different viral features has not been quantified, nor has their effectiveness been definitively established, largely because of difficulties surrounding econometric identification of endogenous peer effects. We therefore designed a randomized field experiment on a popular social networking website to test the effectiveness of a range of viral messaging capabilities in creating peer influence and social contagion among the 1.4 million friends of 9,687 experimental users. Overall, we find that viral product design features can indeed generate econometrically identifiable peer influence and social contagion effects. More surprisingly, we find that passive-broadcast viral messaging generates a 246% increase in local peer influence and social contagion effects, while adding active-personalized viral messaging only generates an additional 98% increase in contagion. Although active-personalized messaging is more effective in encouraging adoption per message and is correlated with more user engagement and sustained product use, passive-broadcast messaging is used more often enough to eclipse those benefits, generating more total peer adoption in the network. In addition to estimating the effects of viral product design on social contagion and product diffusion, our work also provides a model for how randomized trials can be used to identify peer influence effects in networks.

Happy House: Spousal Weight and Individual Well-Being

We use life satisfaction and Body Mass Index (BMI) information from three waves of the SOEP to test for social interactions in BMI between spouses. Social interactions require that the cross-partial effect of partner’s weight and own weight in the utility function be positive. Using life satisfaction as a utility proxy, semi-parametric regressions show that the correlation between satisfaction and own BMI is initially positive, but turns negative after some threshold. Critically, this latter threshold increases with partner’s BMI when the individual is overweight. The negative well-being impact of own BMI is thus lower when the individual’s partner is heavier, which is consistent with social contagion effects in weight. However, this cross-partial effect becomes insignificant in instrumental variable regressions, suggesting that the uninstrumented relationship reflects selection on the marriage market or omitted variables, rather than social interactions.

Distinguishing Spurious and Real Peer Effects: Evidence from Artificial Societies, Small-Group Experiments, and Real Schoolyards

Abstract In a variety of important domains, there is considerable correlational evidence suggestive of what are variously referred to as social norm effects, contagion effects, information cascades, or peer effects. It is difficult to statistically identify whether such effects are causal, and there are various non-causal mechanisms that can produce such apparent norm effects. Lab experiments demonstrate that real peer effects occur, but also that apparent cascade or peer effects can be spurious. A curious feature of American local school configuration policy provides an opportunity to identify true peer influences among adolescents. Some school districts send 6th graders to middle school (e.g., 6th-8th grade “junior high”); others retain 6th graders for one additional year in K-6 elementary schools. Using administrative data on public school students in North Carolina, we have found that sixth grade students attending middle schools are much more likely to be cited for discipline problems than those attending elementary school, and the effects appear to persist at least through ninth grade. A plausible explanation is that these effects occur because sixth graders in middle schools are suddenly exposed to two cohorts of older, more delinquent peers.

Geographical clustering of eating disordered behaviors in U.S. high school students

The aim of this study was to determine if eating disorder behaviors geographically clustered among U.S high school students. Our sample consisted of 15,349 high school students who responded to the 1999 Youth Risk Behavior Study (YRBS). Weight control and eating disordered behaviors under investigation included dieting, exercising, fasting, using diet pills, and purging to control weight in the last 30 days. We calculated pairwise odds ratios (PWORs) to determine the degree of within-county clustering. Among all participants, adjusted analyses revealed that having any weight control or eating disorder symptom, severe restricting, dieting, exercising, and diet pill use each showed significant clustering (p < .05). Purging did not significantly cluster by county. The magnitude of clustering was stronger for female students than male students. The significant clustering of weight control and eating disorder behavior in U.S. high school students confirms evidence of a social contagion effect of eating disorders.

Social Contagion and Income Heterogeneity in New Product Diffusion: A Meta-Analytic Test

Standard diffusion models capture social contagion only coarsely and do not allow one to operationalize different contagion mechanisms. Moreover, there is increasing skepticism about the importance of contagion and, as has long been known, S-shaped diffusion curves can also result from heterogeneity in the propensity to adopt. We present hypotheses about conditions under which specific contagion mechanisms and income heterogeneity are more pronounced, and test these hypotheses using a meta-analysis of the q/p ratio in applications of the Bass diffusion model. The ratio is positively associated with the Gini index of income inequality in a country, supporting the heterogeneity-in-thresholds interpretation. The ratio also varies as predicted by the Gamma-Shifted Gompertz diffusion model, but the evidence vanishes after controlling for national culture. As to contagion, the q/p ratio varies with the four Hofstede dimensions of national culture—for three of them in a direction consistent with the social contagion interpretation. Furthermore, products with competing standards have a higher q/p ratio, which is again consistent with the social contagion interpretation. Finally, we find effects of national culture only for products without competing standards, suggesting that technological effects and culturally moderated social contagion effects might not operate independently from each other.

Explorations in the social contagion of memory.

Four experiments examined social influence on the development of false memories. We employed the social contagion paradigm: A subject and a confederate see scenes and then later take turns recalling items from the scenes, with the confederate erroneously reporting some items that were not present in the scenes; on a final test, the subject reports these suggested items when instructed to recall only items from the scenes. The first two experiments showed that the social contagion effect persisted when subjects were explicitly warned about the possibility that confederates' responses might induce false memories and when they were tested via source-monitoring tests that explicitly gave the choice of attributing suggested items to the other person. Levels of false recall and recognition increased with the number of times the misleading information was suggested (Experiment 3), and subjects were more likely to incorporate the erroneous responses of an actual confederate on a recognition/source test as compared with those of a simulated confederate (Experiment 4). Collectively, the data support the claim that false memories may be transmitted between people and reveal critical factors that modulate the social contagion of memories.

Grouptask Satisfaction

This article reviews evidence for considering job satisfaction at the group level of analysis. Group-level job satisfaction is functionally independent of individual-level job satisfaction. This construct is labeled group task satisfaction and is defined as the group’s shared attitude toward its task and the associated work environment. The authors propose that group task satisfaction develops out of within-group homogeneity in individual job satisfaction, which in turn is a product of the shared work conditions, social influence processes, attraction-selection-attrition effects, and emotional contagion effects associated with work groups. They predict that through group interaction, the within-group homogeneity in job satisfaction will come to be perceived as a characteristic of the group. Once identified as a group characteristic, group task satisfaction will be subject to processes such as polarization and prototyping, with the result that group task satisfaction should function independently of the mean level of job satisfaction within the group. The authors predict that group task satisfaction will be related to the mean level of individual job satisfaction within the group, the quality of the group’s processes, and the performance of the group, thus serving as an important indicator of team viability.

Social contagion of memory.

We report a new paradigm for studying false memories implanted by social influence, a process we call the social contagion of memory. A subject and confederate together saw six common household scenes (e.g., a kitchen) containing many objects, for either 15 or 60 sec. During a collaborative recall test, the 2 subjects each recalled six items from the scenes, but the confederate occasionally made mistakes by reporting items not from the scene. Some intrusions were highly consistent with the scene schema (e.g., a toaster) while others were less so (e.g., oven mitts). After a brief delay, the individual subject tried to recall as many items as possible from the six scenes. Recall of the erroneous items suggested by the confederate was greater than in a control condition (with no suggestion). Further, this social contagion effect was greater when the scenes were presented for less time (15 sec) and when the intruded item was more schema consistent (e.g., the toaster). As with other forms of social influence, false memories are contagious; one person's memory can be infected by another person's errors.

Increasing Returns and Social Contagion in Cultural Industries

A formal definition of cultural industries is developed following four distinct features of cultural goods: (a) oversupply, (b) quality uncertainty, (c) network effects and (d) demand reversal. Drawing on economic and socio‐psychological notions of ‘network’, increasing returns and social contagion effects are distinguished. Increasing returns may govern the adoption of standards when choices are binary, social contagion explains the diffusion of cultural goods when choices are multiple. Together, the four structural features delineating cultural industries account for curious competitive dynamics prevalent in cultural markets, such as the notorious 10 : 90 proportionality (under which 10% of cultural goods account for 90% of the market), causal ambiguity about the reasons for success, and the formation of fashions. Six managerial recommendations are advanced, focusing on a criticial circulation point triggering self‐sustaining diffusion patterns. Finally ‘project‐based enterprises’ and ‘network forms of governance’ are identified as the organizational forms most suited to the dynamics of the cultural markets.

A Network Analysis of Social Contagion Processes in an Organizational Intervention

Interventions aimed at changing the psychological attributes of individuals who form a social system may be limited by reliance on models and methods which do not account for the effects of social interaction on individual attributes. The use of network analysis to model the effects of social contagion on personal attributes is demonstrated in an evaluation of an organizational intervention. Sociometric indices of the norms created by social contagion predicted subjects' self-perceptions better than either expectations imposed on them in small groups or their own observable behavior. Social contagion stabilized the subjects' self-perceptions over time, despite the efforts of the intervention to change their self-perceptions through small group socialization and organizational restructuring. Network models of social contagion may provide useful tools for the design and evaluation of interventions that aim to change the attributes of individuals who form social systems. Further, these models theoretically integrate social relations and social cognition in a manner that helps to bridge the sociological and psychological study of human relations.

Isolating the Determinants of Innovativeness: A Split-Population Tobit (SPOT) Duration Model of Timing and Volume of First and Repeat Purchase

The authors present the Split-Population Tobit (SPOT) duration model to incorporate two conceptually distinct dimensions of innovativeness in a single framework, namely, the timing and volume of adoption. Rather than utilizing a diffusion model specification based on word-of-mouth and social contagion effects, the present approach uses a growth model specification and delineates a general function of time to describe the distribution of adoption timing. Estimation and several validation exercises performed on a data set describing the diffusion of personal computers across a sample of over 3000 U.S. firms provide strong support for the superiority of the SPOT model over models derived from restricted conceptualizations of innovativeness. The empirical work, albeit modest, tests the impact of covariates, such as firm-size and decision-centralization, on the dimensions of innovativeness and sheds light on some inconsistent findings in the innovation adoption literature. The authors subsequently derive the extended SPOT model (EXT-SPOT) to incorporate repeat purchase volume and timing in the SPOT framework. Finally, they discuss limitations, further research directions, and implications for the practitioner.