Emergent Leadership in Collective Action:
An Experimental Approach
Helen Margetts*, Peter
†
John ,
Stéphane Reissfelder*
*Oxford Internet Institute, University of Oxford †University of Manchester
Introduction and Research Interest
Treatment Conditions
Susceptibility to Treatment and Personality Features
Political mobilization increasingly takes place on-line and there are various
features of on-line mobilization that are reshaping the dynamics of collective
action. First, internet platforms can provide real-time ‘social information’
about the participatory decisions of other people which may influence an
individual’s likelihood of joining the mobilization. Second, they can vary the
extent to which an individual’s decision to participate is made public or visible.
Third, leadership is less costly and activists are likely to depend less on
extensive resources and established networks. We hypothesise that in this
changed environment, charismatic’ leadership is less important and what
matters is the willingness of some individuals to ‘start’ mobilization, which is
then fuelled by social information and visibility. We test this hypothesis in an
experiment where subjects participate in a public goods game under
treatments where social information and visibility are varied. Post-experiment
personality tests enabled us to examine the personality characteristics of those
subjects who habitually ‘lead’ rather than ‘follow’. The research addresses
previous work on leadership and tipping points in collective action (Marwell
and Oliver, 1993; Schelling, 2005).
Three treatments are implemented in addition to a control condition. Control rounds show no
information about the decision of other subjects (anonymity condition). The first treatment shows
information about the total amount raised within the group and the number of contributors (social
information condition). These rounds are limited in time to 50s. The second treatment consists a visual
display of individual contributions on a projector screen (visibility condition). The last treatment is a
combination of the social information and visibility conditions.
Further, we measure the
treatment effects of each
condition, by comparing the
contributions of each subject
under those treatment and the
contributions in the control
round for each scenario (results
summarized in Table 2). The
visibility treatment had a strong
positive effect (+0.96 tokens),
whilst the social information
condition was not unidirectional.
The negative coefficient of the
'rank' variable suggests that the
treatments have more influence
on early movers. Agreement to
the issue was associated with a
Table 2: OLS Predictors of treatment effect
size. Standard errors are clustered by
positive treatment effect, whilst
individuals. N= 3235
subjects who rated the scenarios
to be important tended to give less under treatment than in control rounds. Subjects
with both cooperative and individualist orientations are responsive to treatment cues.
The magnitude of the effects is relative strong, yet they are in opposite directions.
Individualists tend to give more under treatment (possibly encouraged by the initiative
of others) whilst cooperative types tend to contribute less under treatment (e.g.
disillusioned by the low amounts given by others). Individuals who have an external
locus of control are more responsive to treatment conditions (as compared to internal
types) and tend to contribute more as a consequence. Measurement of respondents’
tendency to adopt innovations were done using the joining year to Facebook. This
value was correlated with the susceptibility to treatment effect - a significant
coefficient in contrast to a self-reported measure. Group size is a strong positive
predictor, in that individuals in larger groups are more responsive to treatment
conditions. Figure 3 shows how personality features affect susceptibility to treatment.
Experimental Design
We implement one deviation from the classical public goods scenario, namely
the step-level paradigm – whereby individual members are asked to contribute
to the collective good at a cost and receive a higher return if the number of
participants is higher than a determined point. Further, we mirror the
asynchronous nature of online collective action by implementing a real-time
sequential protocol of play (as one treatment condition), which can capture
the different social information early vs. late potential contributors receive.
We recruited 185 subjects to the OxLAB laboratory. After the experiment,
subjects completed a questionnaire, which notably includes a short personality
survey to determine subjects’ locus of control using the Rotter scale. At each
round (n=28), subjects are shown a step-level public good scenario phrased as
a request to fund a local initiative. Subjects are endowed with 10 tokens and
are informed about the provision point (60 tokens) and the number of
participants in their group (N = 10). If the provision point is met, a fixed bonus
is redistributed amongst all participants. Some sessions were not fully
attended, so smaller groups were formed, in which the provision point was
adjusted to meet 60% of the maximum amount collectable. Subjects are paid
for one round only, which is selected at random, a design which means that
the most rational behaviour is to treat each as if it were the only round
(Bardsley 2000). Groups of 10 are randomly allocated at each round, so that
players never interact with the same exact same group.
Fig.1: Screenshot from the
experimental interface. Here,
the social information treatment
shows the progress of fundraising
round and displays the total
amount raised
Figure 2 (left) shows the distributions of individual contributions broken down by treatment
conditions(across all scenarios). The distribution under the control treatment (light blue) has a tri-modal
shape. A large proportion of subjects contribute either 0 or 10 tokens (although these are not necessarily
their consistent strategy across rounds), and other provide the “fair share” (60% of their endowment)
which correspond to the amount each should contribute for the provision point to be reached at equal
costs. In the social information condition (surface plot in middle), a larger proportion of participants are
inclined to free-ride on the contributions of others by giving 0 tokens. When contributions become
individually visible (dark blue surface), the largest proportion of individuals give 6 tokens, likely due to an
impulse to be seen as contributing their “fair share”. Figure 2 (right) shows the aggregate effects of
treatment conditions on the likelihood that provision points are collectively met across scenarios. The
reasons for these strong differences is explored at the individual and group levels in what follows.
Determinants of Contribution Amount
We seek to identify the factors that determine
individuals’ choice of how much to contribute to each
round and run a tobit regression (summarized in table 1)
which tests personal attributes, group dynamics and
scenario features as predictors for contribution amount.
This analysis reveals that the visibility treatment triggers
a strong impulse to contribute more. The impact of the
social information treatment is captured by the group
dynamics variables: the further from the provision point,
the less individuals will be prepared to give. 'Rank' is the
order at which participants make decisions, the variable
hence shows that earlier contributors are more generous.
Agreement with and importance of scenario will,
predictably, increase the contribution amount. Personlevel features (measured in post-questionnaire) are the
most revealing: Social value orientation (cooperative and
individualistic, as compared to reference category
'inconsistent') is highly indicative of contribution amount.
Individuals who like to take financial risk are willing to
give nearly 1 token more on average. Men give less than
women. Finally, group size (varying from 5 to 10 due to
differential attendance) mattered in that subjects within
larger groups tended to contribute more.
Conclusion
Table 1: OLS Predictors of contribution amount.
Standard errors are clustered by individuals. N= 4550
Investigating the dynamics of on-line mobilization, we found a strong effect of visibility on
an individual’s likelihood of participation, replicating findings of Gerber et al (2008) for a
collective action context. The effect of social information had no overall significance but
rather introduced a strategic element (with both +ve and –ve effects). For combined
treatment effects, the results suggest that people with a co-operative personality, an
internal locus of control and a low tendency for innovation adoption are less susceptible to
changes in the information environment and therefore more likely to participate in the
early stages of mobilizations. Further research of this kind could shed light on the
distribution of ‘k’ in Schelling’s mobilization curve and on the likelihood of the ‘tipping
points’ that he predicted, which our finding that earlier contributors are more
generous appears to contradict.