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Towards Real-time Emergency Response using Crowd
Supported Analysis of Social Media
Jakob Rogstadius, Vassilis Kostakos
Madeira Interactive Technologies Institute
University of Madeira
9000-390 Funchal, Portugal
Jim Laredo, Maja Vukovic
IBM T.J. Watson Research Center
Hawthorne NY 10532, USA
This position paper outlines an ongoing research project
that aims to incorporate crowdsourcing as part of an
emergency response system. The proposed system's novelty
is that it integrates crowdsourcing into its architecture to
analyze and structure social media content posted by
microbloggers and service users, including emergency
response coordinators and victims, during the event or
disaster. An important challenge in this approach is
identifying appropriate tasks to crowdsource, and adopting
effective motivation strategies.
Emergency response, social media, crowdsourcing, text
ACM Classification Keywords
H5.m. Information interfaces and presentation (e.g., HCI):
The period of time following a natural disaster or other
large scale emergency is traditionally characterized by
individuals having limited situational awareness bound to
their immediate surroundings, combined with sparse high
level summaries provided by traditional media. More
recently, during events such as earthquakes, elections,
bushfires and terrorist attacks, people have systematically
chosen to share their knowledge on a micro level with
others through online social media such as Twitter [3,9,10].
In fact, it is often the case that reports of incidents get
published through social media before they reach regular
media. However, despite the timeliness and volume of this
new information source, it is highly challenging for users to
overview and navigate the torrent of information which can
result from such large scale events. In addition, the absence
of summaries and validity checks of claims made by posters
add further complexity to the already challenging task. In
the near future we are likely to see an increase in volume of
produced social media content, thus further increasing the
need for improved structure and overview.
We envision a system design (Figure 1) in which machine
learning and automated tools work hand in hand with a
crowdsourcing community to quickly and efficiently
organize and analyze information on microblogging
websites during crisis and emergency situations. The
system we envision has six main responsibilities or
1. Collect crowd generated data (e.g. by tracking keywords
2. Make a "best attempt" at structuring the data using NLP
and other text mining techniques, as well as extracting
named entities, locations and important points in time.
3. Identify shortcomings in the collected data and the
inferred structure, formulate tasks and seek answers via
a crowdsourcing platform.
4. Integrate the new knowledge provided by the crowd into
the existing knowledge base.
5. Present aggregated and structured data back to the
community, i.e. emergency response professionals,
affected community members and others.
6. Wherever possible, support direct interaction between
users of the presentation layer and the original
Crowd in the loop
Two vital feedback loops exist in this design. The analysis
loop is one where the system gives users an improved
understanding of the event; enabling improved actions and
communication (for instance by directly addressing
messages to service users whose reports have been
collected by the system). This in turn changes the state of
the event, which is reflected by a change in the inflow of
information to the system.
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In the clarification loop, the system identifies information
gaps, contradictions, weaknesses or uncertainties in the
current information coverage of the situation. It then turns
these flaws in the knowledge base into tasks suitable for
crowdsourcing, sends them off to a crowdsourcing engine
and integrates the results back into the knowledge base. We
argue that by merging automatically aggregated information
from social media with the output of crowdsourced work,
the system can have the short processing times and
scalability of an algorithmic approach, combined with the
adaptability of humans. By integrating the crowd into the
analytic process, the system will be able to infer structure in
ways that closely match human cognitive models, even for
topic domains where the training corpora is scarce.
Information generated through crowdsourced tasks should
ideally be fed back into the medium which formed the
original input to the system, to decouple the analysis and
knowledge representation from the presentation layer and
thereby simplifying development of clients for different
technical platforms. In fact, if gathered data and drawn
conclusions can be made publicly available (e.g. as social
media updates or RSS feeds), this knowledge can be
accessed in its raw form through any existing client. For
instance, members of the crowd can be asked to track down
images depicting an event, which the system then
automatically shares through a designated Twitter account.
A significant strength of our proposed system over existing
disaster tracking systems such as Ushahidi
(www.ushahidi.com) is that it listens to communication
channels that people already use in their pre-event lives,
rather than attempting to rally information providers for a
new channel once the event has already taken place. This
social media content is available regardless of the success
and popularity of the system itself and by merely acting as a
crowd-algorithm-powered information catalyst, it becomes
easier to deploy the system in particular during early stages
of an event.
The proposed system builds on existing research in text
mining methods, such as clustering, named entity extraction
and relevance classification, and in particular methods
adapted for social media content [2,5,6]. Furthermore,
crowdsourcing platform design, e.g. Amazon’s Mechanical
Turk (mturk.com) and CrowdFlower (crowdflower.com)
are directly relevant to this work, as are media aggregation
systems such as Twitrix+  and the Europe Media
Monitor . Finally, motivational factors governing the
quality and quantity of crowdsourced work, both of
extrinsic and intrinsic nature [1,4], are directly relevant.
The ongoing research efforts in this project are currently
focused on measuring the interaction effects of intrinsic and
extrinsic motivation on crowdsourced work. In addition, we
are currently adapting text mining methods to streaming
social media, in ways that permit integration of a crowd-in-
the-loop at different stages of the analysis. Finally, we are
in the process of identifying types of crowdsourcing tasks
suitable for being generated by the system.
There exists a series of research challenges that need to be
addressed. In terms of knowledge mining, we believe there
is a need for knowledge representations that support both
the identification of missing information and turning the
gaps into crowdsourced tasks. Additionally, we require
suitable techniques for keyword extraction and pruning for
Figure 1. The proposed system architecture that integrates crowdsourcing into the analysis of social media content. Two feedback
loops are present in the flow of information; the analysis loop and the clarification loop.
high quality topic tracking in real-time, as well as
techniques for capturing the location (and possibly context)
of people contributing information to the system.
In terms of representation, we expect to develop
visualization techniques for the collected data, and suitable
UI’s for commenting and responding to content generated
by others or the system. A further challenge will be the
design of compact and accurate summarizations of large
social media content clusters of similar topic.
Finally, in terms of crowdsourcing, there exists an open
issue of managing the tradeoffs between quality, cost and
time needed to complete tasks, in the context of the varying
priorities that are applicable during disasters. In addition,
the critical information flow in the system must be
algorithmic, as processing bottlenecks are otherwise likely
to appear due to lack of people willing to work, or lack of
incentives to offer the workers. Part of this research must
clearly identify the functionality that belongs to this critical
path and define support tasks that can be delegated to a
crowd. Even if human intelligence is necessary for high
quality output, the system as a whole must still be
functional without workers.
This paper has outlined our ongoing efforts at building a
crowd-powered system for real-time response to emergency
events by analysing information available on social media.
We have outlined a proposed system architecture for
involving crowds in the real-time analysis, and have
designed two important feedback loops. These will enable
a) the system to give users feedback about the status of the
event, and b) the users to give feedback to the system to
improve its analysis. Finally, the paper summarizes our
initial findings, our ongoing efforts, as well as a set of
challenges that we expect to tackle in the future.
This work is funded by an IBM Open Collaboration Award
and by the Portuguese Foundation for Science and
Technology (FCT) grant CMU-PT/SE/0028/2008 (Web
Security and Privacy).
Jakob Rogstadius is pursuing a PhD in HCI at the
University of Madeira, where he conducts research on how
community generated content (such as Twitter) can be
leveraged to create situational awareness in crisis situations
through both crowdsourcing and algorithmic approaches.
Before joining the University of Madeira, he designed
visualization tools and data mining algorithms for a
company in the fuel and energy sector; and he has been
employed as research engineer at Sweden's National Center
for Visual Analytics. He holds a MSc in Media Technology
and Engineering from the University of Linköping,
Sweden, where his final thesis project dealt with applied
Vassilis Kostakos is an Assistant Professor in the Madeira
Interactive Technologies Institute at the University of
Madeira, and an Adjunct Assistant Professor at the Human
Computer Interaction Institute at Carnegie Mellon
University. He received an IBM Open Collaboration Award
in 2010, and is a Fellow of the Finland Distinguished
Professor Program. His research interests include: mobile
and pervasive computing, human-computer interaction,
social networks, crowdsourcing.
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