Summer Projects

Over the summer, Arie Croitoru and myself took part in the George Mason University Aspiring Scientists Summer Internship Program. We worked with three very talented high-school students who over the course of the seven and a half week program produced some excellent research around the areas of agent-based modeling and social media analysis. An overview of their work can be seen in the posters and abstracts that the students produced at the end of the internship.
Lawrence Wang explored how social media could be used with respect to predicting election results under a project entitled “And the Winner Is? Predicting Election Results using Social Media”. Below you can read Lawrence’s abstract and see his poster.

“The 2012 U.S. presidential election demonstrated how Twitter can serve as a widely accessible forum of political discourse. Recently, researchers have investigated whether social media, particularly Twitter, can function as a predictive tool. In the past decade, multiple studies have claimed to successfully predict the results of elections using Twitter data. However, many of these studies fail to account for the inherent population bias present in Twitter data, leading to ungeneralizable results. In this project, I investigate the prospects of using Twitter data as an alternative to poll data for predicting the 2012 presidential election. The tweet corpus consisted of tweets published one month before the November election day. Using VADER, a sentiment analysis tool, I analyzed over 140,000 tweets for political sentiment. I attempted to circumvent the Twitter population bias by comparing age, race, and gender metrics of the Twitter population with that of the U.S. population. Furthermore, I utilized Bayesian inference with prior distributions from the results of the 2008 presidential election in order to mitigate the effects of limited tweet data in certain states. The resulting model correctly predicted the likely outcomes of 46 of the 50 states and predicted that President Obama would be reelected with a probability of 0.945. Such a model could be used to explore the forthcoming elections. ” 

In a second project, Varun Talwar, explored how knowledge bases could be utilized to better contextualize social media discussions with a project entitled “Context Graphs: A Knowledge-Driven Model for Contextualizing Twitter Discourse.” Below you can read Varun’s project abstract and his end of project poster.

Introduction: User posted content through online social media (SM) platforms in recent years has emerged as a rich field for narrative analysis of topics captured during the discussion discourse. In particular, collective discourse has been used to manually contextualize public perception of health related events.

Objective: As SM feeds tend to be noisy, automated detection of the context of a given SM discourse stream has proven to be a challenging task. The primary objective of this research is to explore how existing knowledge bases could be utilized to better contextualize SM discussions through topic modeling and mining. By utilizing such existing knowledge it would then be possible to explore to what extent a given discourse is related to a known or a new context, as well as compare and contrast SM discussions through their respective contexts.

Methods: In order to accomplish these goals this research proposes a novel approach for contextualizing SM discourse. In this approach, topic modeling is combined with a knowledgebase in a two-step process. First, key topics are extracted from a SM data corpus by applying a statistical topic-modeling algorithm, a process that also results in data dimensionality reduction. Once a set of salient topics are extracted, each topic is then used to mine the knowledge base for sub graphs that represent the contextual linkages between knowledge elements. Such sub-graphs can then further disambiguate the topic modeling results, and be utilized for qualifying context similarity across SM discussions.

Results: The time-series analysis of the Twitter discourse via graph-matching algorithms reveals the change in topics as evidenced by the emergence of the terms “pregnancy” and “abortion” as information about the virus propagated through the Twitter community. “

Elizabeth Hu explored the current migration crisis in Europe in a project entitled “Across the Sea: A Novel Agent-Based Model for the Migratory Patterns of the European Refugee Crisis”. Below is Elizabeth’s abstract, poster and an example model run.

“Since 2010, a growing number of refugees have sought asylum in European nations, fleeing violence and military conflict in their home countries. Most of the refugees originate from Syria, Iraq, Afghanistan, and African nations. The vast majority of refugees risk their lives in the popular yet perilous Mediterranean Sea Route often prone to boat accidents and subsequent deaths of migrants.  The flow of millions of refugees has introduced a humanitarian crisis not seen since World War II. European nations are struggling to cope with the influx of refugees through various border policies.

In order to explore this crisis, a geographically explicit agent-based model has been developed to study the past and future patterns of refugee flows. Traditional migration models, which represent the population as an aggregate, fail to consider individual decision-making processes based on personal status and intervening opportunities. However, the novel agent-based model developed here of migration allows population behavior to emerge as the result of individual decisions. Initial population, city, and route attributes are based upon data from the UNHCR, EU agencies, crowd-sourced databases, and news articles. The agents, refugees, select goal destinations in accordance with the Law of Intervening Opportunities. Thus, goals are prone to change with fluctuating personal needs. Agents choose routes not only based on distance, but also other relevant route attributes. The resulting migration flows generated by the model under various circumstances could provide crucial guidance for policy and humanitarian aid decisions.”

The movie below gives a sense of the migration paths the refugees are taking.

Continue reading »

CSS Phds and Masters 2016

One of the great rewards with working within a university is the interaction with students and seeing them advance through their studies and carryout innovative research projects.

This last academic year the Computational Social Science Program here at Mason had a bumper crop of graduates both at the PhD and masters level.

 In the picture are newly hooded Drs Palmer, Rouly and Magallanes.
Along with the not so new Drs Axtell, Crooks and Cioffi.

Our recent PhD graduates included:

       In the picture are newly hooded Drs Scott, Russo, Masad, Dover and Shin. Along with the not so new Drs Cioffi, Crooks,  Kennedy and Mrs. Underwood.

      Along with our PhD graduates we also had a number of Masters students graduate in the MAIS with a Concentration in Computational Social Science Program. Well done to Rui Zhang, Justin Brandenburg, Matthew Oldham, Stefan McCabe, Craig Brown and Stefani Fournier.

      Continue reading »

      CSS Phds and Masters 2016

      One of the great rewards with working within a university is the interaction with students and seeing them advance through their studies and carryout innovative research projects.

      This last academic year the Computational Social Science Program here at Mason had a bumper crop of graduates both at the PhD and masters level.

       In the picture are newly hooded Drs Palmer, Rouly and Magallanes.
      Along with the not so new Drs Axtell, Crooks and Cioffi.

      Our recent PhD graduates included:

           In the picture are newly hooded Drs Scott, Russo, Masad, Dover and Shin. Along with the not so new Drs Cioffi, Crooks,  Kennedy and Mrs. Underwood.

          Along with our PhD graduates we also had a number of Masters students graduate in the MAIS with a Concentration in Computational Social Science Program. Well done to Rui Zhang, Justin Brandenburg, Matthew Oldham, Stefan McCabe, Craig Brown and Stefani Fournier.

          Continue reading »

          A Semester with Urban Analytics

          This past semester I gave a new class at GMU entitled “Urban Analytics”. In a nutshell the class was about introducing students to a broad interdisciplinary field that focuses on the use of data to study cities. More specifcally the emphasis of the cla…

          Continue reading »

          A Semester with Urban Analytics

          This past semester I gave a new class at GMU entitled “Urban Analytics”. In a nutshell the class was about introducing students to a broad interdisciplinary field that focuses on the use of data to study cities. More specifcally the emphasis of the cla…

          Continue reading »

          Call For Papers: Smart Buildings and Cities

          Special Issue on Smart Buildings and Cities for IEEE Pervasive Computing

          Submission deadline: 1 July 2016  Extended to July 18th, 2016
          Publication date: April–June 2017

          One of Mark Weiser’s first envisionments of ubiquitous and pervasive computing had the smart home as its central core. Since then, researchers focused on realizing this vision have built out from the smart home to the smart city. Such environments aim to improve the transparency of information and the quality of life through access to smarter and more appropriate services.

          Despite efforts to build these environments, there are still many unanswered questions: What does it mean to make a building or a city “smart”? What infrastructure is necessary to support smart environments? What is the return on investment of a smart environment?

          The key to building smart environments is the fusion of multiple technologies including sensing, advanced networks, the Internet of Things, cloud computing, big data analytics, and mobile devices. This special issue aims to explore new technologies, methodologies, case studies, and applications related to smart buildings and cities. Contributions may come from diverse fields such as distributed systems, HCI, ambient intelligence, architecture, transportation and urban planning, policy development, and cyber-physical systems. Relevant topics for issue include

          • Applications, evaluations, or case studies of smart buildings/cities
          • Architectures and systems software to support smart environments
          • Big data analytics for monitoring and managing smart environments
          • Economic models for smart buildings/cities
          • Models for user interaction in smart environments
          • Formative studies regarding the design, use, and acceptance of smart services
          • Configuration and management of smart environments
          • Embedded, mobile ,and crowd sensing approaches
          • Cloud computing for smart environments
          • Domain-specific investigations (such as transportation or healthcare)

          The guest editors invite original and high-quality submissions addressing all aspects of this field, as long as the connection to the focus topic is clear and emphasized.

          Guest Editors

          Submission Information

          Continue reading »

          Call For Papers: Smart Buildings and Cities

          Special Issue on Smart Buildings and Cities for IEEE Pervasive Computing

          Submission deadline: 1 July 2016  Extended to July 18th, 2016
          Publication date: April–June 2017

          One of Mark Weiser’s first envisionments of ubiquitous and pervasive computing had the smart home as its central core. Since then, researchers focused on realizing this vision have built out from the smart home to the smart city. Such environments aim to improve the transparency of information and the quality of life through access to smarter and more appropriate services.

          Despite efforts to build these environments, there are still many unanswered questions: What does it mean to make a building or a city “smart”? What infrastructure is necessary to support smart environments? What is the return on investment of a smart environment?

          The key to building smart environments is the fusion of multiple technologies including sensing, advanced networks, the Internet of Things, cloud computing, big data analytics, and mobile devices. This special issue aims to explore new technologies, methodologies, case studies, and applications related to smart buildings and cities. Contributions may come from diverse fields such as distributed systems, HCI, ambient intelligence, architecture, transportation and urban planning, policy development, and cyber-physical systems. Relevant topics for issue include

          • Applications, evaluations, or case studies of smart buildings/cities
          • Architectures and systems software to support smart environments
          • Big data analytics for monitoring and managing smart environments
          • Economic models for smart buildings/cities
          • Models for user interaction in smart environments
          • Formative studies regarding the design, use, and acceptance of smart services
          • Configuration and management of smart environments
          • Embedded, mobile ,and crowd sensing approaches
          • Cloud computing for smart environments
          • Domain-specific investigations (such as transportation or healthcare)

          The guest editors invite original and high-quality submissions addressing all aspects of this field, as long as the connection to the focus topic is clear and emphasized.

          Guest Editors

          Submission Information

          Continue reading »

          Megacities through the Lens of Social Media

          Megacities, which can be roughly defined as cities with a population of over 10 million people are on the increase due to ongoing urbanization trends. The United Nations notes that since the 1970’s the number of megacities has more than tripled (from 8 to 34), and is expected to further double until 2050 (to exceed 60).

          The question we are wondering is how can GeoSocial analysis help understand such cities. To this end, we have recently had a paper published  entitled: “Megacities: Through the Lens of Social Media” in the Journal of the Homeland Defense and Security Information Analysis Center (HDIAC). In the paper we discuss opportunities and challenges that social media brings with respect to understanding the physical and cyber spaces within megacities. Below you can see the synopsis to our paper.

          Due to ongoing urbanization trends the worldwide urban population is projected to grow from half of the global population (today) to two thirds of it by 2030. Almost all the new megacities that will emerge through this process are in geopolitical hotspots of southeast Asia and sub-Saharan Africa. Therefore, the U.S. Department of Defense must consider the challenges presented by engagement in such environments when planning for the future. The physical challenge of operating in such dense, highly three-dimensional, environments is only compounded by the added challenge presented by the advanced functional complexity of these environments: megacities function at the intersection of the physical, social, and cyber spaces. Accordingly, military operations in these locations must prepare to engage in environments where news, ideas, and opinions are shaped in cyberspace and propagated across the physical urban landscape. As social networks connect (or, often, divide) populations they form communities and facilitate their mobilization.

          We have observed these processes time and again, from the streets of Cairo during the Arab Spring, to the streets of Tokyo during the Fukushima nuclear disaster, and the streets of Paris during the recent ISIL terrorist attacks. Advancing our capability to analyze crowd-generated content in the form of social media feeds is a substantial scientific challenge with considerable implications for future DoD operations. In this publication, we use representative examples to demonstrate the opportunities and challenges associated with such information, especially as they relate to large urban areas. 

          An emerging framework to study urban systems.

          Social networks embedded within a geographical content, leading to connected, non-contiguous areas.

          Full Reference: 

          Stefanidis, A., Jenkins A., Croitoru, A. and Crooks, A. (2016). “Megacities Through the Lens of Social Media”, Journal of the Homeland Defense & Security Information Analysis Center (HDIAC), 3(1): 24-29. (pdf)

          Continue reading »

          Megacities through the Lens of Social Media

          Megacities, which can be roughly defined as cities with a population of over 10 million people are on the increase due to ongoing urbanization trends. The United Nations notes that since the 1970’s the number of megacities has more than tripled (from 8 to 34), and is expected to further double until 2050 (to exceed 60).

          The question we are wondering is how can GeoSocial analysis help understand such cities. To this end, we have recently had a paper published  entitled: “Megacities: Through the Lens of Social Media” in the Journal of the Homeland Defense and Security Information Analysis Center (HDIAC). In the paper we discuss opportunities and challenges that social media brings with respect to understanding the physical and cyber spaces within megacities. Below you can see the synopsis to our paper.

          Due to ongoing urbanization trends the worldwide urban population is projected to grow from half of the global population (today) to two thirds of it by 2030. Almost all the new megacities that will emerge through this process are in geopolitical hotspots of southeast Asia and sub-Saharan Africa. Therefore, the U.S. Department of Defense must consider the challenges presented by engagement in such environments when planning for the future. The physical challenge of operating in such dense, highly three-dimensional, environments is only compounded by the added challenge presented by the advanced functional complexity of these environments: megacities function at the intersection of the physical, social, and cyber spaces. Accordingly, military operations in these locations must prepare to engage in environments where news, ideas, and opinions are shaped in cyberspace and propagated across the physical urban landscape. As social networks connect (or, often, divide) populations they form communities and facilitate their mobilization.

          We have observed these processes time and again, from the streets of Cairo during the Arab Spring, to the streets of Tokyo during the Fukushima nuclear disaster, and the streets of Paris during the recent ISIL terrorist attacks. Advancing our capability to analyze crowd-generated content in the form of social media feeds is a substantial scientific challenge with considerable implications for future DoD operations. In this publication, we use representative examples to demonstrate the opportunities and challenges associated with such information, especially as they relate to large urban areas. 

          An emerging framework to study urban systems.

          Social networks embedded within a geographical content, leading to connected, non-contiguous areas.

          Full Reference: 

          Stefanidis, A., Jenkins A., Croitoru, A. and Crooks, A. (2016). “Megacities Through the Lens of Social Media”, Journal of the Homeland Defense & Security Information Analysis Center (HDIAC), 3(1): 24-29. (pdf)

          Continue reading »

          AAG: Symposium on Human Dynamics Research – Urban Analytics

          Urban Analytics Sessions @ the AAG 2016
           
          As part of the Symposium on Human Dynamics Research we have organized three great sessions sessions relating to Urban Analytic which will take place on Thursday, 3/31/2016, from 1:20 PM – 7:00 PM in Union Square 18, Hilton Hotel, 4th Floor.
          Session Description: A deluge of new data created by people and machines is changing the way that we understand, organize and model urban spaces. New analytics are required to make sense of these data and to usefully apply findings to real systems. This session seeks to bring together quantitative or mixed methods papers that develop or use new analytics in order to better understand the form, function and future of urban systems. We invite methodological, theoretical and empirical papers that engage with any aspect of urban analytics. Topics include, but are not limited to:
          • New methodologies for tackling large, complex or dirty data sets;
          • Case studies involving analysis of novel or unusual data sources;
          • Policy analysis, predictive analytics, other applications of data;
          • Intensive modelling or simulation applied to urban areas or processes;
          • Individual-level and agent-based models (ABM) of geographical systems;
          • Validating and calibrating models with novel data sources;
          • Ethics of data collected en masse and their use in simulation and analytics.

          Organizers:

          3445 Symposium on Human Dynamics Research: Urban Analytics (I)

          Thursday, 3/31/2016, from 1:20 PM – 3:00 PM in Union Square 18, Hilton Hotel, 4th Floor

          Chair:Nick Malleson

          Talks:

          Discussant: Mark Birkin

          3545 Symposium on Human Dynamics Research: Urban Analytics (II)

          Thursday, 3/31/2016, from 3:20 PM – 5:00 PM in Union Square 18, Hilton Hotel, 4th Floor

          Chair: Paul Longley

          Talks:

          3645 Symposium on Human Dynamics Research: Urban Analytics (III) 

          Thursday, 3/31/2016, from 5:20 PM – 7:00 PM in Union Square 18, Hilton Hotel, 4th Floor

          Chair: Andrew Crooks

          Talks:

          Discussant: Andrew Crooks 

          Continue reading »

          AAG: Symposium on Human Dynamics Research – Urban Analytics

          Urban Analytics Sessions @ the AAG 2016
           
          As part of the Symposium on Human Dynamics Research we have organized three great sessions sessions relating to Urban Analytic which will take place on Thursday, 3/31/2016, from 1:20 PM – 7:00 PM in Union Square 18, Hilton Hotel, 4th Floor.
          Session Description: A deluge of new data created by people and machines is changing the way that we understand, organize and model urban spaces. New analytics are required to make sense of these data and to usefully apply findings to real systems. This session seeks to bring together quantitative or mixed methods papers that develop or use new analytics in order to better understand the form, function and future of urban systems. We invite methodological, theoretical and empirical papers that engage with any aspect of urban analytics. Topics include, but are not limited to:
          • New methodologies for tackling large, complex or dirty data sets;
          • Case studies involving analysis of novel or unusual data sources;
          • Policy analysis, predictive analytics, other applications of data;
          • Intensive modelling or simulation applied to urban areas or processes;
          • Individual-level and agent-based models (ABM) of geographical systems;
          • Validating and calibrating models with novel data sources;
          • Ethics of data collected en masse and their use in simulation and analytics.

          Organizers:

          3445 Symposium on Human Dynamics Research: Urban Analytics (I)

          Thursday, 3/31/2016, from 1:20 PM – 3:00 PM in Union Square 18, Hilton Hotel, 4th Floor

          Chair:Nick Malleson

          Talks:

          Discussant: Mark Birkin

          3545 Symposium on Human Dynamics Research: Urban Analytics (II)

          Thursday, 3/31/2016, from 3:20 PM – 5:00 PM in Union Square 18, Hilton Hotel, 4th Floor

          Chair: Paul Longley

          Talks:

          3645 Symposium on Human Dynamics Research: Urban Analytics (III) 

          Thursday, 3/31/2016, from 5:20 PM – 7:00 PM in Union Square 18, Hilton Hotel, 4th Floor

          Chair: Andrew Crooks

          Talks:

          Discussant: Andrew Crooks 

          Continue reading »

          Call for Papers: GeoSocial: Social Media and GIScience

          GeoSocial: Social Media and GIScience


          A GIScience 2016 Workshop

          September 27th, Montreal, Canada

          This day-long workshop aims to serve as a platform to discuss and showcase the complex issues associated with the analysis of social media contributions in the context of GIScience.

          Spanning spatial footprints, social networks, and sociocultural themes, such data can support a variety of applications, ranging from disaster response and environmental monitoring to health informatics and digital citizenship. Given their variations in accuracy, the complex patterns of participation, and the constantly increasing data volumes, analyzing such data in a meaningful, reliable, and timely manner is a substantial challenge. The objective of this workshop is to showcase on-going research in the GIScience community on the analysis of social media content and thus support the emergence of a cohesive research agenda in our community.

          We invite submissions of short papers (1,500-2,000 words) that present research related to the workshop theme. Examples of topics of particular interest include:

          • Theoretical/conceptual issues in linking social media with GIScience.
          • Accuracy and reliability issues associated with the analysis of social media content.
          • Analysis of the spatial and spatiotemporal patterns of social networks.
          • Geocoding methods and engines for social media messages.
          • GeoSocial Analytic software and tool development.
          • Visualization of multi-thematic geosocial content.
          • Computational challenges associated with the big data nature of such information.
          • Social multimedia: images and videos.
          • Applications and case studies. 

          Workshop Format:

          • This full day workshop will comprise presentations of research based on short paper submissions, as well as a break-out group session will be held in the afternoon, followed by a plenary synthesis session, addressing a “GeoSocial Research Agenda”. 

          Organizers:

          Website: http://geosocialanalysis.blogspot.com/p/about.html

            Continue reading »

            Call for Papers: GeoSocial: Social Media and GIScience

            GeoSocial: Social Media and GIScience


            A GIScience 2016 Workshop

            September 27th, Montreal, Canada

            This day-long workshop aims to serve as a platform to discuss and showcase the complex issues associated with the analysis of social media contributions in the context of GIScience.

            Spanning spatial footprints, social networks, and sociocultural themes, such data can support a variety of applications, ranging from disaster response and environmental monitoring to health informatics and digital citizenship. Given their variations in accuracy, the complex patterns of participation, and the constantly increasing data volumes, analyzing such data in a meaningful, reliable, and timely manner is a substantial challenge. The objective of this workshop is to showcase on-going research in the GIScience community on the analysis of social media content and thus support the emergence of a cohesive research agenda in our community.

            We invite submissions of short papers (1,500-2,000 words) that present research related to the workshop theme. Examples of topics of particular interest include:

            • Theoretical/conceptual issues in linking social media with GIScience.
            • Accuracy and reliability issues associated with the analysis of social media content.
            • Analysis of the spatial and spatiotemporal patterns of social networks.
            • Geocoding methods and engines for social media messages.
            • GeoSocial Analytic software and tool development.
            • Visualization of multi-thematic geosocial content.
            • Computational challenges associated with the big data nature of such information.
            • Social multimedia: images and videos.
            • Applications and case studies. 

            Workshop Format:

            • This full day workshop will comprise presentations of research based on short paper submissions, as well as a break-out group session will be held in the afternoon, followed by a plenary synthesis session, addressing a “GeoSocial Research Agenda”. 

            Organizers:

            Website: http://geosocialanalysis.blogspot.com/p/about.html

              Continue reading »

              Call For Papers: Rethinking the ABCs

              Readers of the blog might be interested in a workshop being organized by Daniel Brown, Eun-Kyeong Kim, Liliana Perez, and Raja Sengupta entitled:

              Rethinking the ABCs: Agent-Based Models and Complexity Science in the age of Big Data, CyberGIS, and Sensor networks

              September 27th, 2016 in Montreal, Canada

              To quote from the call:

              “A broad scope of concepts and methodologies from complexity science – including Agent-Based Models, Cellular Automata, network theory, chaos theory, and scaling relations – has contributed to a better understanding of spatial/temporal dynamics of complex geographic patterns and process.

              Recent advances in computational technologies such as Big Data, Cloud Computing and CyberGIS platforms, and Sensor Networks (i.e. the Internet of Things) provides both new opportunities and raises new challenges for ABM and complexity theory research within GIScience. Challenges include parameterization of complex models with volumes of georeferenced data being generated, scale model applications to realistic simulations over broader geographic extents, explore the challenges in their deployment across large networks to take advantage of increased computational power, and validate their output using real-time data, as well as measure the impact of the simulation on knowledge, information and decision-making both locally and globally via the world wide web.

              The scope of this workshop is to explore novel complexity science approaches to dynamic geographic phenomena and their applications, addressing challenges and enriching research methodologies in geography in a Big Data Era.”

              More information about the workshop can be found at https://sites.psu.edu/bigcomplexitygisci/

              Continue reading »

              Call For Papers: Rethinking the ABCs

              Readers of the blog might be interested in a workshop being organized by Daniel Brown, Eun-Kyeong Kim, Liliana Perez, and Raja Sengupta entitled:

              Rethinking the ABCs: Agent-Based Models and Complexity Science in the age of Big Data, CyberGIS, and Sensor networks

              September 27th, 2016 in Montreal, Canada

              To quote from the call:

              “A broad scope of concepts and methodologies from complexity science – including Agent-Based Models, Cellular Automata, network theory, chaos theory, and scaling relations – has contributed to a better understanding of spatial/temporal dynamics of complex geographic patterns and process.

              Recent advances in computational technologies such as Big Data, Cloud Computing and CyberGIS platforms, and Sensor Networks (i.e. the Internet of Things) provides both new opportunities and raises new challenges for ABM and complexity theory research within GIScience. Challenges include parameterization of complex models with volumes of georeferenced data being generated, scale model applications to realistic simulations over broader geographic extents, explore the challenges in their deployment across large networks to take advantage of increased computational power, and validate their output using real-time data, as well as measure the impact of the simulation on knowledge, information and decision-making both locally and globally via the world wide web.

              The scope of this workshop is to explore novel complexity science approaches to dynamic geographic phenomena and their applications, addressing challenges and enriching research methodologies in geography in a Big Data Era.”

              More information about the workshop can be found at https://sites.psu.edu/bigcomplexitygisci/

              Continue reading »

              “Space, the Final Frontier”: How Good are Agent-Based Models at Simulating Individuals and Space in Cities?

              Recently, Alison Heppenstall, Nick Malleson  and myself have just had a paper accepted in Systems entitled: “Space, the Final Frontier”: How Good are Agent-Based Models at Simulating Individuals and Space in Cities?” In the paper we critically examine how well agent-based models have  simulated a variety of urban processes. We discus what considerations are needed when choosing the appropriate level of spatial analysis and time frame to model urban phenomena and what role Big Data can play in agent-based modeling. Below you can read the abstract of the paper and see a number of example applications discussed.

              Abstract: Cities are complex systems, comprising of many interacting parts. How we simulate and understand causality in urban systems is continually evolving. Over the last decade the agent-based modeling (ABM) paradigm has provided a new lens for understanding the effects of interactions of individuals and how through such interactions macro structures emerge, both in the social and physical environment of cities. However, such a paradigm has been hindered due to computational power and a lack of large fine scale datasets. Within the last few years we have witnessed a massive increase in computational processing power and storage, combined with the onset of Big Data. Today geographers find themselves in a data rich era. We now have access to a variety of data sources (e.g., social media, mobile phone data, etc.) that tells us how, and when, individuals are using urban spaces. These data raise several questions: can we effectively use them to understand and model cities as complex entities? How well have ABM approaches lent themselves to simulating the dynamics of urban processes? What has been, or will be, the influence of Big Data on increasing our ability to understand and simulate cities? What is the appropriate level of spatial analysis and time frame to model urban phenomena? Within this paper we discuss these questions using several examples of ABM applied to urban geography to begin a dialogue about the utility of ABM for urban modeling. The arguments that the paper raises are applicable across the wider research environment where researchers are considering using this approach.

              Keywords: cities; agent-based modeling; big data; crime; retail; space; simulation

              Figure 1. (A) System structure; (B) System hierarchy; and (C) Related subsystems/processes (adapted from Batty, 2013).

              Reference cited:

              Batty, M. (2013).  The New Science of Cities; MIT Press: Cambridge, MA, USA.

              Full reference to the open access paper:

              Heppenstall, A., Malleson, N. and Crooks A.T. (2016). “Space, the Final Frontier”: How Good are Agent-based Models at Simulating Individuals and Space in Cities?, Systems, 4(1), 9; doi: 10.3390/systems4010009 (pdf)

               

              Continue reading »

              “Space, the Final Frontier”: How Good are Agent-Based Models at Simulating Individuals and Space in Cities?

              Recently, Alison Heppenstall, Nick Malleson  and myself have just had a paper accepted in Systems entitled: “Space, the Final Frontier”: How Good are Agent-Based Models at Simulating Individuals and Space in Cities?” In the paper we critically examine how well agent-based models have  simulated a variety of urban processes. We discus what considerations are needed when choosing the appropriate level of spatial analysis and time frame to model urban phenomena and what role Big Data can play in agent-based modeling. Below you can read the abstract of the paper and see a number of example applications discussed.

              Abstract: Cities are complex systems, comprising of many interacting parts. How we simulate and understand causality in urban systems is continually evolving. Over the last decade the agent-based modeling (ABM) paradigm has provided a new lens for understanding the effects of interactions of individuals and how through such interactions macro structures emerge, both in the social and physical environment of cities. However, such a paradigm has been hindered due to computational power and a lack of large fine scale datasets. Within the last few years we have witnessed a massive increase in computational processing power and storage, combined with the onset of Big Data. Today geographers find themselves in a data rich era. We now have access to a variety of data sources (e.g., social media, mobile phone data, etc.) that tells us how, and when, individuals are using urban spaces. These data raise several questions: can we effectively use them to understand and model cities as complex entities? How well have ABM approaches lent themselves to simulating the dynamics of urban processes? What has been, or will be, the influence of Big Data on increasing our ability to understand and simulate cities? What is the appropriate level of spatial analysis and time frame to model urban phenomena? Within this paper we discuss these questions using several examples of ABM applied to urban geography to begin a dialogue about the utility of ABM for urban modeling. The arguments that the paper raises are applicable across the wider research environment where researchers are considering using this approach.

              Keywords: cities; agent-based modeling; big data; crime; retail; space; simulation

              Figure 1. (A) System structure; (B) System hierarchy; and (C) Related subsystems/processes (adapted from Batty, 2013).

              Reference cited:

              Batty, M. (2013).  The New Science of Cities; MIT Press: Cambridge, MA, USA.

              Full reference to the open access paper:

              Heppenstall, A., Malleson, N. and Crooks A.T. (2016). “Space, the Final Frontier”: How Good are Agent-based Models at Simulating Individuals and Space in Cities?, Systems, 4(1), 9; doi: 10.3390/systems4010009 (pdf)

               

              Continue reading »

              Measles Vaccination Narrative in Twitter

              A summary of our approach
              Continuing our work with respects to GeoSocial analysis we have recently published a paper in JMIR Public Health and Surveillance entitled “The Measles Vaccination Narrative in Twitter: A Quantitative Analysis“. In this paper we explore how social media can be quantitatively studied to explore the narrative behind measles vaccinations. Below you can read the abstract to the paper which includes the background to why we chose to study this topic, the study objective, our methodology, a summary of our results and conclusions. 

              Background: The emergence of social media is providing an alternative avenue for information exchange and opinion formation on health-related issues. Collective discourse in such media leads to the formation of a complex narrative, conveying public views and perceptions.

              Objective: This paper presents a study of Twitter narrative regarding vaccination in the aftermath of the 2015 measles outbreak, both in terms of its cyber and physical characteristics. The contributions of this work are the analysis of the data for this particular study, as well as presenting a quantitative interdisciplinary approach to analyze such open-source data in the context of health narratives.

              Methods: 669,136 tweets were collected in the period February 1 through March 9, 2015 referring to vaccination. These tweets were analyzed to identify key terms, connections among such terms, retweet patterns, the structure of the narrative, and connections to the geographical space.

              Results: The data analysis captures the anatomy of the themes and relations that make up the discussion about vaccination in Twitter. The results highlight the higher impact of stories contributed by news organizations compared to direct tweets by health organizations in communicating health-related information. They also capture the structure of the anti-vaccination narrative and its terms of reference. Analysis also revealed the relationship between community engagement in Twitter and state policies regarding child vaccination. Residents of Vermont and Oregon, the two states with the highest rates of non-medical exemption from school-entry vaccines nationwide, are leading the social media discussion in terms of participation.

              Conclusions: The interdisciplinary study of health-related debates in social media across the cyber-physical debate nexus leads to a greater understanding of public concerns, views, and responses to health-related issues. Further coalescing such capabilities shows promise towards advancing health communication, supporting the design of more effective strategies that take into account the complex and evolving public views of health issues.

              Global distribution of tweets in our data corpus
              The paper is open access and can be viewed and downloaded from here.
              Full reference:

              Radzikowski, J., Stefanidis, A., Jacobsen K.H., Croitoru, A., Crooks, A.T. and Delamater, P.L. (2016). “The Measles Vaccination Narrative in Twitter: A Quantitative Analysis”, JMIR Public Health and Surveillance, 2(1):e1. 

              Hashtag associations: clustering based on co-occurrences of hashtags in individual tweets
              Continue reading »

              Measles Vaccination Narrative in Twitter

              A summary of our approach
              Continuing our work with respects to GeoSocial analysis we have recently published a paper in JMIR Public Health and Surveillance entitled “The Measles Vaccination Narrative in Twitter: A Quantitative Analysis“. In this paper we explore how social media can be quantitatively studied to explore the narrative behind measles vaccinations. Below you can read the abstract to the paper which includes the background to why we chose to study this topic, the study objective, our methodology, a summary of our results and conclusions. 

              Background: The emergence of social media is providing an alternative avenue for information exchange and opinion formation on health-related issues. Collective discourse in such media leads to the formation of a complex narrative, conveying public views and perceptions.

              Objective: This paper presents a study of Twitter narrative regarding vaccination in the aftermath of the 2015 measles outbreak, both in terms of its cyber and physical characteristics. The contributions of this work are the analysis of the data for this particular study, as well as presenting a quantitative interdisciplinary approach to analyze such open-source data in the context of health narratives.

              Methods: 669,136 tweets were collected in the period February 1 through March 9, 2015 referring to vaccination. These tweets were analyzed to identify key terms, connections among such terms, retweet patterns, the structure of the narrative, and connections to the geographical space.

              Results: The data analysis captures the anatomy of the themes and relations that make up the discussion about vaccination in Twitter. The results highlight the higher impact of stories contributed by news organizations compared to direct tweets by health organizations in communicating health-related information. They also capture the structure of the anti-vaccination narrative and its terms of reference. Analysis also revealed the relationship between community engagement in Twitter and state policies regarding child vaccination. Residents of Vermont and Oregon, the two states with the highest rates of non-medical exemption from school-entry vaccines nationwide, are leading the social media discussion in terms of participation.

              Conclusions: The interdisciplinary study of health-related debates in social media across the cyber-physical debate nexus leads to a greater understanding of public concerns, views, and responses to health-related issues. Further coalescing such capabilities shows promise towards advancing health communication, supporting the design of more effective strategies that take into account the complex and evolving public views of health issues.

              Global distribution of tweets in our data corpus
              The paper is open access and can be viewed and downloaded from here.
              Full reference:

              Radzikowski, J., Stefanidis, A., Jacobsen K.H., Croitoru, A., Crooks, A.T. and Delamater, P.L. (2016). “The Measles Vaccination Narrative in Twitter: A Quantitative Analysis”, JMIR Public Health and Surveillance, 2(1):e1. 

              Hashtag associations: clustering based on co-occurrences of hashtags in individual tweets
              Continue reading »
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