The Digital Evolution of Occupy Wall Street
Michael D. Conover*, Emilio Ferrara, Filippo Menczer, Alessandro Flammini
Center for Complex Networks and Systems Research, School of Informatics and Computing, Indiana University, Bloomington, Indiana, United States of America
Abstract
We examine the temporal evolution of digital communication activity relating to the American anti-capitalist movement
Occupy Wall Street. Using a high-volume sample from the microblogging site Twitter, we investigate changes in Occupy
participant engagement, interests, and social connectivity over a fifteen month period starting three months prior to the
movement’s first protest action. The results of this analysis indicate that, on Twitter, the Occupy movement tended to elicit
participation from a set of highly interconnected users with pre-existing interests in domestic politics and foreign social
movements. These users, while highly vocal in the months immediately following the birth of the movement, appear to
have lost interest in Occupy related communication over the remainder of the study period.
Citation: Conover MD, Ferrara E, Menczer F, Flammini A (2013) The Digital Evolution of Occupy Wall Street. PLoS ONE 8(5): e64679. doi:10.1371/
journal.pone.0064679
Editor: Matjaz Perc, University of Maribor, Slovenia
Received February 12, 2013; Accepted April 16, 2013; Published May 29, 2013
This is an open-access article, free of all copyright, and may be freely reproduced, distributed, transmitted, modified, built upon, or otherwise used by anyone for
any lawful purpose. The work is made available under the Creative Commons CC0 public domain dedication.
Funding: The authors gratefully acknowledge support from the National Science Foundation (grant CCF-1101743), the Defense Advanced Research Projects
Agency (DARPA) (grant W911NF-12-1-0037), and the McDonnell Foundation. The funders had no role in study design, data collection and analysis, decision to
publish, or preparation of the manuscript.
Competing Interests: The authors have declared that no competing interests exist.
* E-mail:
[email protected]
tion relating to the news media and narrative frames such as ‘‘We
are the 99%,’’ suggesting that long-distance communication on
Twitter played a role in the collective framing processes that
imbue social movements with a shared language, purpose and
identity. This evidence indicates that Occupy participants used the
Twitter platform to address critical issues facing any burgeoning
social movement, and that during peak periods these streams were
rich with actionable, relevant information.
To establish the extent of Occupy participant engagement with
Twitter over time, here we study the total amount of Occupyrelated traffic on the platform from September 2011 through
September 2012. With respect to this measure of activity, we find
that Occupy traffic has diminished by orders of magnitude relative
to peak activity volumes in late 2011. This effect is evident even in
concerted attempts to revive the movement’s flagging levels of
engagement, with activity returning to baseline within a week of
May 1st, 2012 reoccupation efforts.
Finding little evidence of sustained activity, we turn our
attention to Occupy participants themselves, in hopes of understanding how these users were changed as a result of engaging with
the movement online. Using a random sample of 25,000 Occupy
users, we study changes in behavior at the individual level with
respect to attention allocation and social connectivity. From this
analysis we are left to conclude that, on Twitter, Occupy evoked
interest from a highly-interconnected community of users with
pre-existing interest in domestic politics and foreign social
movements. Though we find statistically significant changes in
political interests and social connectivity over the study period, the
magnitude of these changes pales in comparison to the amount of
attention these individuals allocated to the Occupy Wall Street
cause.
Introduction
Information communications technologies play a crucial role in
the development and persistence of many modern social movements [1–3]. Among these, the American anti-capitalist movement
Occupy Wall Street (‘Occupy’) is remarkable for the prominent
role social media, and in particular Twitter, played in facilitating
communication among its participants [4,5]. Functioning as a
high-visibility forum in which adherents and prospective participants could interact and share information, Twitter represented a
valuable resource for supporting the movement’s political and
social objectives. In time, however, activity on the platform
substantially diminished, mirroring the fading prominence of
protest action on the ground. In light of this decline, we seek to
understand more about the population from which Occupy drew
its support, and specifically whether these individuals exhibited
changes in behavior or social connectivity over the course of the
movement’s evolution.
The Twitter platform, like other information communication
technologies, has the potential to confer a number of benefits to
burgeoning social movements [6–8]. Chief among these is the
opportunity to connect individuals in service of the dual goals of
resource mobilization and collective framing [9]. These factors,
well studied in the social sciences literature, are critical to the
success of social movements. Resource mobilization refers to the
process whereby a social movement works to marshal the physical
and technological infrastructure, human resources, and financial
capital necessary to sustain its ongoing activity [10,11]. Collective
framing refers to the social processes whereby movement
participants negotiate the shared language and narrative frames
that help define the movement’s identity and goals [12,13].
In related work [9], we report on evidence that Occupy users
leveraged Twitter to communicate, at the local level, time-sensitive
information about protest and police action. We also find that
users relied on these channels to facilitate interstate communicaPLOS ONE | www.plosone.org
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The Digital Evolution of Occupy Wall Street
random sample of 25,000 random users who produced at least one
tweet in the Occupy corpus. We then produced a second corpus
containing any tweet, regardless of content, produced by each
account in this sample during the 15-month period spanning June
1st, 2011 through August 31st, 2012. Including tweets from the
three-month period preceding the start of the Occupy Wall Street
movement allows us to study the behavior of these users before,
during, and after the movement’s primary period of activity.
Referred to hereafter as the random sample, this dataset contains
approximately 7.74 million tweets produced by 25,000 unique
users.
To facilitate analysis relating to the attention allocation habits of
these individuals, we rely on three non-overlapping sets of
hashtags: those related to Occupy Wall Street (defined above), a
second set relating to foreign social movements, and a third
relating to domestic political communication. As we are interested
exclusively in the attention allocation habits of Occupy users, we
identified the set of hashtags relating to domestic political
communication and foreign social movements by manually
inspecting the 300 hashtags most frequently used by individuals
in the random sample. Table 1 lists the hashtags associated with
each topic. While not exhaustive due to a long-tail use distribution,
the 300 most popular hashtags account for 70.8% of all tagging
activity, with the 300th most popular tag constituting just 0.027%
of all tags. We therefore believe that the inclusion of additional
tags in our topic lists is not likely to affect the results of this study.
Materials and Methods
Twitter Platform
Twitter is a social networking platform that allows individuals to
consume content from and contribute content to streams
comprised of 140-character messages known as tweets [14]. The
Twitter stream has been extensively explored in the recent
literature, with focus on user activity modeling [15–19], content
classification [20–23], sentiment analysis [24–26] and event
detection [27–29]. Broadly speaking, there are two types of
content streams: those associated with individual accounts and
those associated with topic-specific tokens known as hashtags. By
following one or more accounts, a user creates a personalized feed
that aggregates into a single, private stream the content produced
by the followed accounts. Hashtags, short tokens prepended with a
pound sign (e.g., #taxes or #obama), allow the content produced
by many individuals to be aggregated into a public, topic-specific
stream including all the tweets containing a given token.
Although by default each user’s tweets are publicly visible, the
audience for an individual’s content is largely limited to his or her
network of immediate followers, attaining greater levels of visibility
only when it is rebroadcast by large numbers of other users. By
including a hashtag in a tweet, however, an individual can
contribute content to a high-profile stream, and thereby engage
with users who might never otherwise see the content. It is this
kind of communication, which represents engagement with a
topically cohesive community of users unconstrained by social
network structure, that is the primary focus of this study.
In addition to engaging with different content streams, users can
interact with one another in two primary ways. A user can retweet
content produced by another individual, rebroadcasting it to his or
her audience of followers, or mention another user in a tweet, which
functions as a publicly-visible message targeting that individual.
Methods
All of the analyses in this article rely on time series describing
changes to measured quantities over the course of the study
period. Each time series is produced by computing a single statistic
on disjoint sets of tweets partitioned into adjacent, temporally nonoverlapping bins of k hours. For all of these analyses we use one of
three temporal resolutions to reveal different characteristics of the
signal under study: 12 hours, 24 hours, or one week.
At various times over the course of the study period, our system
experienced service outages that affected our ability to collect data
from the Twitter API. Amounting to 15 days in total, these periods
are: September 29 to October 4, 2011; October 11–12, 2011;
December 28–30, 2011; February 11–13, 2012; February 16–17,
2012; and May 28–31, 2012. Owing to the fact that the measures
we employ reflect relative composition of the stream rather than its
absolute volume, these outages do not unduly influence the
statistical character of our results.
Data
We rely on two primary datasets extracted over a 15-month
period from an approximately 5–10% sample of the entire public
Twitter stream (https://dev.twitter.com/docs/streaming-apis/
streams/public). In addition to information about the content
and users associated with a tweet, the Twitter streaming API
provides timestamp metadata that allow for the historical
reconstruction of the time series presented in this study.
To identify Occupy-related content, we deem relevant any
tweet containing a hashtag matching either #ows or #occupy*,
where * represents a wildcard character. This set includes highprofile tags such as #occupy as well as location-specific tokens
such as #occupyoakland and #occupyseattle. While this approach does not allow us to study content that does not contain an
Occupy-specific hashtag, we argue that it is appropriate for two
reasons. As outlined above, hashtags allow a user to reach an
audience beyond his or her immediate followers, and it is this kind
of expressly public engagement in which we are primarily
interested. Moreover, while topic modeling techniques may allow
for the analysis of untagged tweets, their use would introduce noise
that could cloud the interpretation of any analytical results [30].
Based on the criteria outlined above, we produce a corpus of all
sampled tweets containing at least one of these hashtags from the
year-long period between September 1st, 2011 to August 31st,
2012. Referred to hereafter as the Occupy corpus, this dataset
contains approximately 1.82 million tweets produced by 447,241
distinct accounts.
In addition to changes in activity explicitly related to the
Occupy movement, we are also interested in changes to the
behavior of individual users over time. To this end, we identified a
PLOS ONE | www.plosone.org
Results
Let us first focus to the total number of tweets in the Occupy
corpus over the course of the year. Figure 1 shows that, in general,
Occupy traffic closely mirrors activity on the ground, and is
characterized by peak levels during the month-long period
following the movement’s initial protests, with significantly
diminished activity levels over the following eleven months. In
terms of relative change, average levels of Occupy traffic in the
second half of the period from September 17th, 2011 to August
31st, 2012 decreased 80.8% relative to the first half of the same
period.
In light of this finding, we wish to gain insights into the
character of the individuals from which Occupy drew its support.
We begin by studying how Occupy user interests changed in time,
examining the frequency with which 25,000 random individuals
produced content relating to one of three topics: Occupy Wall
Street, foreign social movements, and domestic politics. Based on
the random sample described in }Data, the results of this analysis
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The Digital Evolution of Occupy Wall Street
describe activity from June 1, 2011 to August 31, 2012, a period
including the three months prior to the initial protest action.
As we are interested in the behavior of individuals who were
active on Twitter at a given time, we identify the set of users Ui
from whom we observe at least one tweet at time step i, regardless
of its content. Within this set we isolate, at each timestep, the set of
users Uit from whom we observe, in any of their tweets, at least
one hashtag relating to topic t. The engaged user ratio DUit D=DUi D
describes the extent to which individuals chose to engage in
communication relating to each of the three topic areas.
Among the set of users engaged with a topic, we next examine
the extent to which that topic tends to dominate their content
production activity. To accomplish this, let us consider, for each
user u[Uit , the collection Hiu of hashtags contained in his or her
tweets at time step i. From this we compute the proportion of each
user’s tagging activity that is associated with a given topic,
DHiut D=DHiu D, where Hiut is the set of tags from topic t produced by u
at time step i. Averaging this value across all engaged users
provides a lens on the behavior of these individuals as a whole, and
is reported as the engaged user attention ratio. Figure 2 presents this
value alongside the engaged user ratio to show how the amount of
attention allocated to the three topics changed over time.
As expected, a large fraction of users produced Occupy related
content during the period of peak activity, with more than 40% of
sampled users allocating on average 64% of their attention to the
topic during the third week following the initial protests. However,
this intense focus on the subject is not sustained over the course of
the following year, with the engaged user ratio decaying to less
than 5% in the last three months of the study period. Moreover,
comparing the engaged user attention ratios from the first half of
the period following the initial Occupy protests (m~:439) to those
from the second half (m~:318), we find that individuals who
continue to produce Occupy content do so with significantly lower
frequency. Computed using a two location t-test for a difference in
sample means, we reject the null hypothesis (pv10{3 ) that the
mean of the engaged user attention ratios in the first half of the
study period is greater than or equal to that of the observations in
the second half of the study period, a finding suggestive of
diminished enthusiasm even among the most persistent individuals.
With respect to foreign social movements and domestic political
communication, we observe that users who would go on to engage
Table 1. Lists of topic-specific hashtags.
Domestic Politics
Social Movements
#tcot
#syria
#p2
#bahrain
#teaparty
#egypt
#gop
#yemen
#anonymous
#libya
#obama
#tahrir
#tlot
#wiunion
#jobs
#iranelection
#ronpaul
#assange
#romney
#wikileaks
#sopa
#jan25
#ndaa
#14feb
#obama2012
#assad
#ocra
#greece
#twisters
#damascus
#sgp
#gaddafi
#politics
#feb14
#solidarity
#scaf
#gop2012
#antisec
#p21
#arabspring
#topprog
#tunisia
#obamacare
#noscaf
#mapoli
#syrian
#acta
#sotu
#newt
#santorum
#mittromney
#gopdebate
#dem
Hashtags were manually selected from among the 300 most frequently used by
individuals in the 25,000-person random sample of Occupy users.
doi:10.1371/journal.pone.0064679.t001
Figure 1. Total number of tweets related to Occupy Wall Street between September 2011 and September 2012. Each timestep
represents a 12-hour period, with vertical blue bars overlaid on periods during which access to the Twitter streaming API was interrupted. Large
bursts in activity tend to correspond to protest or police action on the ground, demarcated with circles. From left to right, the events are: initial
Occupy Wall Street protest in Zuccotti Park; initial NYPD arrests of protesters; march from Foley Square to Zuccotti Park; protest at U.S. Armed Forces
recruiting station in Times Square; protest in support of Iraq veteran injured by police-fired projectile; NYPD action to clear Zuccotti Park; protest
against eviction from Zuccotti Park; first round of Egyptian elections; ‘May Day’ general strike and planned reoccupation of former encampments.
doi:10.1371/journal.pone.0064679.g001
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Figure 2. Attention allocation of 25,000 randomly selected Occupy users to each of three topics: Occupy Wall Street, domestic
politics, and revolutionary social movements. Engaged User Ratio describes the proportion of active users in each timestep who produced at
least one topically-relevant tweet. Engaged User Attention Ratio describes, among these users, the share of average attention allocated to each topic.
The Engaged User Attention Ratio did not exhibit meaningful trends for either domestic politics or foreign social movements, and so it is omitted
from the figure for sake of visual clarity. Refer to } Results for the full derivation of these measures. The dashed vertical line corresponds to the date of
the first Occupy protest.
doi:10.1371/journal.pone.0064679.g002
from an already tightly interconnected community of users, rather
than uniting disparate social groups behind a common cause.
with the Occupy movement online tended to exhibit interest in
these topics before the initial protest activity in September, 2011.
Comparing the engaged user ratios in the first 12 weeks of the
study period with those observed during the last 12 weeks of the
study period, we find a significant but small increase in domestic
political communication activity. This conclusion is based on a two
location t-test for a difference in sample means, in which we reject
the null hypothesis (pv10{3 ) that the mean of the engaged user
ratios from the first twelve weeks (m~0:066) is greater than or
equal to that of the latter half of the study period (m~0:077). With
respect to interest in foreign social movements, we observe a
significant (pv0:05) but small decrease in engagement for the
same periods (from m~0:074 to m~0:057). These differences
suggest that the changes in individual behaviors in response to the
Occupy Wall Street movement were limited.
Finally, let us examine the extent to which Occupy users tended
to interact with one another over the course of the study period.
To this end we focus on the proportion of retweets and mentions
produced by active users in the random sample that involved
another user who produced at least one Occupy-related tweet
during the year following the movement’s inception. This
proportion is computed with respect to all of a user’s retweets
and mentions, regardless of content, rather than just those related
to Occupy Wall Street. Inspecting the 95% confidence interval
bands in Figure 3 we observe a statistically significant increase in
in-group retweet and mention activity during the peak period of
Occupy activity, followed by a gradual decay to values approaching pre-Occupy levels. Comparing the fifteen week period before
the inception of the movement to the fifteen week period at the
study’s close, we use a two location t-test to identify a small but
significant increase in both in-group retweets (pv10{6 ) and
mentions (pv10{3 ), with the mean connectivity increasing 5.1%
for retweets and 3.2% for mentions. Although these changes are
statistically significant, they can hardly be interpreted as evidence
that this community’s long-term social connectivity has been
dramatically altered in response to participation in the Occupy
Wall Street movement. Moreover, it’s notable that even in the
period preceding the Occupy events, nearly 30% of these
individuals’ targeted retweeting activity and almost a quarter of
their mentioning were originated from or were directed to other
Occupy users, suggesting that the movement elicited engagement
PLOS ONE | www.plosone.org
Discussion
While interest and activity relating to the Occupy movement
has substantially diminished, one could envision that increased
levels of engagement with the political process online might
constitute a positive outcome for the movement’s participants.
Along these lines, however, Occupy users remain barely changed,
exhibiting a slight increase in attention paid to domestic politics
and a slight decrease in attention paid to foreign social
movements. Relative to the dramatic behavioral changes these
users exhibited in the early stages of the movement, and the
magnitude of Occupy-related communication in general, these
changes constitute a somewhat underwhelming long-term effect.
Similarly, a supporter of the movement might take as a
promising outcome increased levels of interaction among Occupy
users. Such a scenario could indicate that these individuals formed
a more tight-knit community over the course of the year, creating
social and communication bonds that may help to facilitate the
efficient spread of information, potentially even reinforcing
individual propensity for offline activity [31,32]. The data,
however, provide little evidence to indicate that Occupy precipitated a dramatic rewiring of these users’ information sharing
networks. While we observe significant increases in the proportion
of in-group retweet and mention activity during the movement’s
peak, the trend suggests that these values are slowly returning to
those observed before the movement’s birth. What’s more, in the
months preceding the initial protests we find evidence indicating
that these users were already highly interconnected, with more
than a quarter of their directed communication (either retweeting
or mentioning) involving another individual who would go on to
create Occupy related content.
Taken together, these data suggest that, on Twitter, the Occupy
movement tended to elicit participation from a set of highly
interconnected users with pre-existing interests in domestic politics
and foreign social movements. These same users, while highly
vocal in the months immediately following the movement’s birth,
appear to have lost interest in Occupy-related communication
over the remainder of the study period, and have exhibited only
marginal changes in their attention allocation habits and social
connectivity as a result of their participation.
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The Digital Evolution of Occupy Wall Street
Figure 3. Proportion of all retweet and mention traffic, regardless of content, from 25,000 randomly selected Occupy users
involving another individual who produced at least one Occupy-related tweet. Shown are means and 95% confidence intervals for each
time step. The dashed vertical line corresponds to the date of the first Occupy protest.
doi:10.1371/journal.pone.0064679.g003
These findings should not be taken to suggest that the Occupy
movement itself has failed, as an argument can be made that the
movement played a role in increasing the prominence of social and
economic inequality in the public discourse. Though it would be
unreasonable to argue that users could have maintained the
frenetic pace of Occupy’s earliest days, it is doubtless that
supporters may have hoped for a more sustained discourse than
is evident from the near-complete abandonment of these once
high-profile communication channels.
Acknowledgments
Thanks to Twitter for making data available through their streaming API;
and to Karissa McKelvey, Clayton Davis, Bruno Gonçalves, Jacob
Ratkiewicz, and other current and past members of the Truthy Project
at Indiana University (cnets.indiana.edu/groups/nan/truthy) for facilitating access to this data.
Author Contributions
Conceived and designed the experiments: MDC EF FM AF. Performed
the experiments: MDC EF. Analyzed the data: MDC EF FM AF. Wrote
the paper: MDC EF FM AF.
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