Occupy Wall Street movement via Twitter

Following on from our work on harvesting ambient geospatial information (AGI) from social media feeds we have started to explore the Occupy Wall Street movement. The movie below shows just one part of this work, specifically the movement of the protesters in New York during the Action Day (November 17) from Wall Street to Brooklyn Bridge. The red dots denote locations of the tweets. Selected tweets are displayed at the bottom of the screen. Active tweets are marked with a white star.

More ananylsis to follow...

New GeoMason Models

We been working on adding more spatial agent based models examples to GeoMason, the GIS extension for MASON. These include a vegetation growth model utilizing raster data and a simple disease outbreak model utilizing vector data. See below for more details.

Vegetation Growth Model:

Eastern Africa has undergone sustained drought for over a decade placing a great strain on the local population. This demo introduces an agent-based model of grazing called Turkana South. The model makes use of NDVI data and monthly rainfall data to drive vegetation growth. After describing the model, the paper investigates the effect rainfall has on carrying capacity and how carrying capacity varies based on initial starting conditions. I conclude that carrying capacity is independent of initial population size.

Disease Outbreak:

This demo introduces a new agent-based model (ABM) for studying the spread of influenza through the schools and households of Fairfax County, VA. It is intended to explore the following questions. How does an epidemic outbreak spread through a school system? What containment approaches might be most effective at stopping an outbreak?

To find out more about GeoMason (including the data and source code for these models) click here. 

Thanks to Joseph Harrison for sharing these models which where developed for class projects at the Department of Computational Social Science at George Mason University.

Harvesting ambient geospatial information from social media feeds

A paper I  recently co-authored with Anthony Stefanidis and Jacek Radzikowski from George Mason University entitled "Harvesting ambient geospatial information from social media feeds" is now available in  GeoJournal. 

 

The abstract for the paper reads as follows: "Social media generated from many individuals is playing a greater role in our daily lives and provides a unique opportunity to gain valuable insight on information flow and social networking within a society. Through data collection and analysis of its content, it supports a greater mapping and understanding of the evolving human landscape. The information disseminated through such media represents a deviation from volunteered geography, in the sense that it is not geographic information per se. Nevertheless, the message often has geographic footprints, for example, in the form of locations from where the tweets originate, or references in their content to geographic entities. We argue that such data conveys ambient geospatial information, capturing for example, people’s references to locations that represent momentary social hotspots. In this paper we address a framework to harvest such ambient geospatial information, and resulting hybrid capabilities to analyze it to support situational awareness as it relates to human activities. We argue that this emergence of ambient geospatial analysis represents a second step in the evolution of geospatial data availability, following on the heels of volunteered geographical information."

Geolocating pairs of tweeters and retweeters

Project Geppetto

Project Geppetto from Autodesk attempts to make it it easy, fast, and fun to add crowds to 3ds Max scenes. It is part of Autodesk's  "People Power" concept, where the basic idea is to try to assemble all the components one needs to create, manage, and control large crowds of characters. Specificcally it attempts to create believable motion, allow for cultural influences (Evolver) and to create a framework for thousands of characters to interact in. Below are some examples of the project.

Book: Agent-Based Models of Geographical Systems

Agent-Based Models of Geographical Systems, is editied by Alison Heppenstall, Andrew Crooks,  Linda See and Mike Batty; and brings together a comprehensive set of papers on the background, theory, technical issues and applications of agent-based modelling (ABM) within geographical systems. This collection of papers (see below) is an invaluable reference point for the experienced agent-based modeller as well those new to the area. Specific geographical issues such as handling scale and space are dealt with as well as practical advice from leading experts about designing and creating ABMs, handling complexity, visualising and validating model outputs. With contributions from many of the world’s leading research institutions (see map below), the latest applied research (micro and macro applications) from around the globe exemplify what can be achieved in geographical context.

This book is relevant to researchers, postgraduate and advanced undergraduate students, and professionals in the areas of quantitative geography, spatial analysis, spatial modelling, social simulation modelling and geographical information sciences.

To see a sample of the book click here.

Book Contents:

Part 1: Computational Modelling: Techniques for Simulating Geographical Systems

1. Perspectives on Agent-Based Models and Geographical Systems.
2. A Generic Framework for Computational Spatial Modelling.
3. A Review of Microsimulation and Hybrid Agent Based Approach.
4. Cellular Automata in Urban Spatial Modelling.
5. Introduction to Agent-Based Modelling.

Part 2: Principles and Concepts of Agent-Based Modelling.

6. Agent-Based Models - Because they're Worth it?
7. Agent-Based Modelling and Complexity.
8. Designing and Building an Agent-Based Model.
9. Modelling Human Behaviour in Agent-Based Models.
10. Calibration and Validation of Agent-Based Models of Land Cover Change.
11. Networks in Agent-Based Social Simulation.

Part 3: Methods, Techniques and Tools for the Design and Construction of Agent-Based Models:

12. The Integration of Agent-Based Modelling and Geographical Information for Geospatial Simulation.
13. Space in Agent-Based Models.
14. Large Scale Agent-Based Modelling: A Review and Guidelines for Model Scaling.
15. Uncertainty and Error.
16. Agent-Based Extensions to a Spatial Microsimulation Model of Demographic Change.
17. Designing, Formulating, and Communicating Agent-Based Models.
18. Agent Tools Techniques and Methods for Macro and Microscopic Simulation.

Part 4: Fine-Scale, Micro Applications of Agent-Based Models:

19. Using Agent-Based Models to Simulate Crime.
20. Urban Geosimulation.
21. Applied Pedestrian Modelling.
22. Business Applications and Research Questions using Spatial Agent-Based Models.
23. Using Agent-Based Models for Education Planning. Is the UK Education System Agent Based?
24. Simulating Spatial Health Inequalities.
25. ABM of Residential Mobility, Housing Choice and Regeneration.
26. Do Land Markets Matter? A Modelling Ontology and Experimental Design to Test the Effects of Land Markets for an Agent-Based Model of Ex-urban Residential Land-Use Change.
27. Exploring Coupled Housing and Land Market Interactions Through an Economic Agent-Based Model (CHALMS).

Part 5: Linking Agent-Based Models to Aggregate Applications Macro:

28. Exploring Urban Dynamics in Latin American Cities using an Agent-Based Simulation Approach.
29. An Agent-Based/Network Approach to Spatial Epidemics.
30. An Agent-Based Modelling Application of Shifting Cultivation.
31. Towards New Metrics for Urban Road Networks. Some Preliminary Evidence from Agent-Based Simulations.
32. A Logistic Based Cellular Automata Model for Continuous Urban Growth Simulation: A Case Study of the Gold Coast City, Australia.
33. Exploring Demographic and Lot Effects in an ABM/LUCC of Agriculture in the Brazilian Amazon.
34. Beyond Zipf: An Agent Based Understanding of City Size Distributions.
35. The Relationship of Dynamic Entropy Maximising and Agent Based Approaches in Urban Modelling.
36. Multi-Agent System Modelling for Urban Systems: The Series of SIMPOP Models.
37. Reflections and Conclusions: Geographical Models to Address Grand Challenges.

Reviews of the book:

By José Manuel Galán for Journal of Artificial Societies and Social Simulation:

"To sum up, this book is an essential reference for any researcher in the field of ABM and geographical systems. Although a more than 700 pages book can scare everyone, the admirably collective effort to synthesize and provide an up-to-date overview of the most relevant methodological and applied works in the field is worth the challenge. Furthermore, it must be said that it can also be recommended to any reader interested in ABM in general, even if initially unconcerned about geographical applications. Indeed, the first book section covers most of the relevant topics to be considered as a primer in ABM, regardless of the context of application, especially the second ("Principles and Concepts of Agent-Based Modelling") and many chapters of the third part ("Methods, Techniques and Tools for the Design and Construction of Agent-Based Models")."

By Itzhak Benenson for International Journal of Geographical Information Science:

"To conclude, the 37 chapters of this fundamental volume provide a comprehensive perspective of the state of the art in the intensively developing field of modern geographic enquiry to the community of Agent-Based (AB) modelers in geography. I enjoyed reading the book and I am sure it will have an essential influence on the AB modeling community and inspire numerous further developments in the field."

By Suzana Dragićević for Environment and Planning B: 

"Overall, this edited book provides a comprehensive overview of the emerging area of ABM. Together, the chapters provide a rich source of bibliographic references, detailed illustrations to support visual understanding, and a logical presentation of the science behind ABM. This would make the book useful for a variety of target audiences ranging from established professionals who are interested in the current state of ABM to graduate and undergraduate students who need a systematic introduction to ABM. This book will be an essential reference text for academics, students, and decision makers who design and interpret spatial models to understand geographical processes."

World Map of authors who contributed to Agent-Based Models of Geographical Systems


View Contributors to Agent-Based Models of Geographical Systems in a larger map    
To see a sample of the book click here.