The dynamics of audience applause

David J. T. Sumpter,Richard P. Mann,Jolyon Faria,Jens Krause

doi:10.1098/rsif.2013.0466

Abstract

The study of social identity and crowd psychology looks at how and why individual people change their behaviour in response to others. Within a group, a new behaviour can emerge first in a few individuals before it spreads rapidly to all other members. A number of mathematical models have been hypothesized to describe these social contagion phenomena, but these models remain largely untested against empirical data. We used Bayesian model selection to test between various hypotheses about the spread of a simple social behaviour, applause after an academic presentation. Individuals' probability of starting clapping increased in proportion to the number of other audience members already ‘infected’ by this social contagion, regardless of their spatial proximity. The cessation of applause is similarly socially mediated, but is to a lesser degree controlled by the reluctance of individuals to clap too many times. We also found consistent differences between individuals in their willingness to start and stop clapping. The social contagion model arising from our analysis predicts that the time the audience spends clapping can vary considerably, even in the absence of any differences in the quality of the presentations they have heard.

Highlights

Mathematical models of social contagion have been suggested for everything from pop songs and fashion to divorce and suicide [1,2,3]
Does the probability of social infection increase in proportion to the number already infected, as it does in most models of disease epidemics? Or is there a tipping point at which infection takes off? Do fashions die out because they have been around for too long or is there a socially mediated ‘recovery’? Are local neighbours or the proportion of the total population who are infected most important in spreading ideas?
Unlike studies focused on visual information, where local transmission of information is between local neighbours [18 –20], we find in our experiments that spatial proximity is not important

Summary

Introduction

Mathematical models of social contagion have been suggested for everything from pop songs and fashion to divorce and suicide [1,2,3]. Each social contagion model has its own set of assumptions about how individuals are ‘infected’ by others [4] These assumptions have not been tested experimentally, leaving several key empirical questions unanswered about how humans respond to each other [5]. Each clap produced by an individual provides us with a time point at which he or she remains ‘infected’ by appreciation, and cessation of clapping denotes ‘recovery’. This type of datum allows us to apply a Bayesian model selection approach to determine the dynamics of how social cues spread through group members. As with any other statistical method, we cannot conclusively rule out the influence of unobserved confounding

Methods

Results

Conclusion