Wednesday, October 31, 2012

Book Reivew: Modeling and Simulating Urban Processes

Recently I reviewed a book for JASSS entitled "Modeling and Simulating Urban Processes" edited by Andreas Koch and Peter Mandl. The full review can be found here.

Modelling and Simulating Urban Processes brings together six papers ranging from spatial-econometric models to geostatistical techniques and multi-agent systems, to analyse and visualise patterns of social organisation, individual behaviour and spatial fabrics to explore urban change. As the preface to the edited volume states: "Modelling and (geo-)simulation techniques offer a wide range of opportunities which cannot completely or adequately be accomplished by traditional quantitative or qualitative methods". The remainder of the book follows up on this discussion in more details.

Overall, the book is well written and referenced which allows the reader to delve deeper into any of the topics discussed. As the papers are longer than those of typical journal articles, it allows the authors to describe the literature and the models in more detail than is normally possible and presents a good survey into the state of the art for modelling and simulating a variety of urban processes.

New Paper: Agent-based modeling of Slums

We have just had a  paper published in Journal of Artificial Societies and Social Simulation the entitled "Slumulation: An Agent-Based Modeling Approach to Slum Formations". This paper adds to the small but growing body of agent-based models exploring slums. Below is the abstract from the paper:
Slums provide shelter for nearly one third of the world's urban population, most of them in the developing world. Slumulation represents an agent-based model which explores questions such as i) how slums come into existence, expand or disappear ii) where and when they emerge in a city and iii) which processes may improve housing conditions for urban poor. The model has three types of agents that influence emergence or sustenance of slums in a city: households, developers and politicians, each of them playing distinct roles. We model a multi-scale spatial environment in a stylized form that has housing units at the micro-scale and electoral wards consisting of multiple housing units at the macro-scale. Slums emerge as a result of human-environment interaction processes and inter-scale feedbacks within our model.

This paper is a starting point for a recently awarded a National Science Foundation grant entitled "An Integrated Simulation Framework to Explore Spatio-Temporal Dynamics of Slum Formation".  Moreover, anyone wanting to run or download the model can do so here.

Full reference:
Patel, A., Crooks, A.T. and Koizumi, N. (2012), Slumulation: an Agent-based Modeling Approach to Slum Formations, Journal of Artificial Societies and Social Simulation, 15 (4). Available at

Tuesday, October 23, 2012

GeoMason Cookbook

While GeoMason is still undergoing development. Mark Coletti has put together a Cookbook for 'recipes' for using GeoMason. The Cookbook is available from  here.

It gives examples of how to read and write geospatial data along with using geospatial data within your agent-based model (e.g. having an agent follow a gradient) and much more. Each example is associated with a GeoMason model example.

Mark welcomes any comments so please send them. For example, what GIS functions  do you want more information on? What are the common problems you have encountered using GeoMason?

Thursday, October 18, 2012

Research Update

With the semester now well underway, I have been reflecting on some of the recent work we have been doing at George Mason University. This is currently taking two strands, the first being agent-based modeling and the second being deriving information from social media. Hopefully by the end of the semester, these two strands will be merged together.

One of the models we are working on is the movement of people across national boarders. Below is a visualization of our work looking at the movement of people across the US/Mexico border which a specific focus on Arizona.

Moreover, we have continued to work diseases and refugee camps. We are scaling up the model to represent the entire population of the Dadaab refugee camps along with verifying the model and exploring the spatial characteristics of the model (i.e the spread of cholera). If anyone will be at the annual North American Meetings of the Regional Science Association International in Ottowa  Canada feel free to come and listen to our presentation. The movie directly below shows the spread of cholera in one camp, while the second movie shows how cholera can be spread throughout the camps by people becoming infected and moving between the different camps.

Some of this work has been feated in UPMagazine and Trajectory Magazine:

Metcalfe, M. (2012), The Bounds of Rationality, UP Magazine, May, Issue 5: 40-43.
Quinn, K. (2012), Visualizing the Invisible:GMU Pioneers a New Approach to Harvesting GEOINT, Trajectory Magazine, Fall, 11-12.

Wednesday, October 17, 2012

Model Replication via OpenABM

The OpenABM website is a great resource for agent-based modelers, I often suggest to my students to visit the site to see the range of possibilities to which agent-based models can be used for.

Recently it was announced that the winner of CoMSES Net Model Recovery and Replication Drive was Torsten Hagerstrand's 1965 Spatial Innovation Diffusion Model. To quote from the announcement it is the "Earliest known calibrated and validated simulation with implicit "agent based" methodology." Sean Bergin replicated the model and provides a great ODD documentation of the model. More  details can be found here.

The OpenABM site has many models which one can view, download and experiment with, including a replication of the Artificial Anasazi model of Axtell et al., (2002) by  Marco Janssen.

Monday, October 15, 2012

USGIF 2012 Achievement Award for Academic Research

The United States Geospatial Intelligence Foundation (USGIF), has just awarded our team the 2012 USGIF Achievement Award for Academic Research for our pioneering work on harvesting geospatial intelligence from social media. This pioneering work has led to the new computational paradigm of GeoSocial Analysis, providing a new understanding of sociocultural dynamics in space and the links among various locations. Below is the movie from the awards ceremony at the GEOINT 2012 Symposium.

Also our work has recently been been featured in the the USGIF Trajectory Magazine.  The first article entitled "OSINT Goes Social: Social media presents new opportunities and challenges for deriving open source intelligence" by Jim Hodges, discusses the potential of social media for open source intelligence.

In the second article entitled "Visualizing the Invisible" by Kristin Quinn discuses how our pioneering work is leading to a new approach to harvesting GEOINT.

Call for Papers: Agent-Based Models of Geographical Systems

Call for Papers: Agent-Based Models of Geographical Systems
IGU Leeds, Applied GIS and Spatial Modelling: 29 May – 2 June 2013

The use of agent-based models is now becoming widespread within the social sciences. With the maturity of these methodologies, there has been an accompanying development in applications for exploring a wide range of geographical, and more broadly, social sciences problems facing society.

The aim of this session is to bring together researchers who are using ABM within the context of Applied GIS or Spatial Modelling.  Papers which explore the relationships between ABM and other related techniques such as spatial microsimulation or cellular automata, and their uses within policy frameworks of substantive applications to geographical problems, will be particularly welcome.
Specific areas of interest include the following:
  • Linking ABM to GIScience and visualization of models and their outputs
  • Work concerned with the calibration, verification and validation of models, or the development of appropriate methods such as genetic algorithms and other geocomputational methods
  • The use of models alongside new forms of data such as social media or volunteered geographical information
  • Representations of agent behavior within geographical systems
  • Substantive applications to geographical problems and policy issues
  • Papers which explore the interactions and linkages to other methods and techniques

Important Dates:
  • Abstract submission: 250 – 300 words before Dec 01 2012
  • Notification: before Feb 01 2013
  • Conference dates: May 29th – 2nd June 2013, Leeds, UK.