Agent-Based Models and Geographical Systems Session at AAG

AAG 2012 - CALL FOR PAPERS

SPECIAL SESSION(S): Agent-Based Models and Geographical Systems


LOCATION AND DATES
Association of American Geographers Annual Meeting
February, 24-28th, 2012, New York, USA


DESCRIPTION
Agent-based modeling (ABM) within geographical systems is starting to mature as a methodology in geography and across the social sciences. The aim of this session(s) is to bring together researchers utilizing agent-based models (and associated methodologies) to discuss topics relating to: theory, technical issues and applications domains of ABM within geographical systems.

We would particularly welcome papers relating to:

• Validation, verification and calibration of Agent-based models
• Hybrid modeling approaches (e.g. utilizing Cellular Automata, Spatial Interaction, Microsimulation, etc.)
• Handling scale and space issues
• Visualization of agent-based models (along with their outputs)
• Ways of representing behavior within models of geographical systems
• Participatory modeling and simulation
• Applications: Ranging from the micro to macro scale

Please e-mail the abstract and key words with your expression of intent to Alison Heppenstall <A.J.Heppenstall@leeds.ac.uk> by September 15th, 2011. Please make sure that your abstract conforms to the AAG guidelines in relation to title, word limit and key words and as specified at <http://www.aag.org/cs/annualmeeting/call_for_papers/abstract_guidelines>. An abstract should be no more than 250 words that describes the presentation's purpose, methods, and conclusions as well as to include keywords. Full submissions will be given priority over submissions with just a paper title.

We are currently investigating journals (e.g. Environment and Planning B) in order to widely disseminate the ideas emerging from this session(s).  Authors will have the opportunity to suitably revise their presentations for publication.

ORGANIZERS:

Alison Heppenstall, School of Geography, University of Leeds, Leeds, UK .

Andrew Crooks, Krasnow Institute for Advanced Study, George Mason University, USA,

Linda See, International Institute of Applied Systems Analysis (IIASA), Laxenburg, Austria

Mark Birkin, School of Geography, University of Leeds, Leeds, UK .

Michael Batty, Centre for Advanced Spatial Analysis (CASA), University College London, London, UK

TIMELINE:

September 15th, 2011: Abstract submission and expression of intent to session organizers. E-mail Alison Heppenstall <A.J.Heppenstall@leeds.ac.uk> by this date if you are interested in being in this session. Please submit an abstract and key words with your expression of intent. Full submissions will be given priority over submissions with just a paper title.

September 22th, 2011: Session finalization. Session organizers determine session order and content and notify authors.

September 26th, 2011: Final abstract submission to AAG, via www.aag.org. All participants must register individually via this site. Upon registration you will be given a participant number (PIN). Send the PIN and a copy of your final abstract to Alison Heppenstall . Neither the organizers nor the AAG will edit the abstracts.

September 28th, 2011: AAG registration deadline. Sessions submitted to AAG for approval.

February 24-28th, 2012: AAG meeting, New York, USA

5th Annual French Complex Systems Summer School

This might be of interest to some.

5th Annual French Complex Systems Summer School

"Complex Systems and Complex Networks"

Paris, July 4th to 16th, 2011

Website: http://iscpif.fr/CSSS2011

The school will provide in-depth reference courses to a multi-disciplinary audience of researchers and students. The level of lectures will range from introductory to advanced, as attendees are not expected to be familiar with all the fields covered. Lecture topics will address specific complex systems methods and tools and their relevance to various disciplines (physics, biology, computer science, geography, sociology, linguistic, etc.). An emphasis will be given to complex networks both as objects of study and as a framework for modeling social and natural phenomena.

Group projects

During the school participants will have to conduct a group project to which about 50% of their time will be dedicated. Small size groups will be constituted on the basis of personal motivations. Groups will have to present their project collectively at the end of school. According to group preferences, projects will be oriented towards some particular aspects of complex networks and particular objects: dynamics reconstruction from data, network analysis and visualization (GEPHI), modeling (NetLogo). Distributed computing facilities will be made available for projects (OpenMole), so that projects requiring intensive simulations and processing can be led.

Tutorials

Specific tutorials (GEPHI, NetLogo and OpenMole) will be given, so that attendees could quickly converge towards the required knowledge on these shared platforms. Each work group will be followed daily by a dedicated teacher, to make sure methodological and technical gaps are filled in. Therefore, no specific knowledge, either in GEPHI, NetLogo or OpenMole is required to attend this school.

This new series of international Complex Systems Summer School (CSSS2011) is organized by the Complex Systems Institute Paris Île-de-France (ISC-PIF), in coordination with the overarching National Network of Complex Systems (RNSC) and & the Complex Systems Institute Rhône-Alpes (IXXI). Our Summer School is also one of the "Thematic School" supported by the CNRS.

The summer school will take place in Paris at the ISC-PIF: 57-59 rue Lhomond,75005, Paris, France

Invited Teachers

Lectures

• Marc barthelemy, CEA (IPhT)/EHESS (CAMS), France
• Nathalie Corson, Laboratoire de Mathématiques Appliquées du Havre, France
• René Doursat, ISC-PIF, France
• Sebastian Grauwin, ENS Lyon/IXXI, France
• Jean-Loup Guillaume, LIP6, France
• Hidde de Jong, INRIA, France
• Luciano Pietronero, Physics Department, Rome University "La Sapienza", Italy
• Camille Roth, CAMS/ISC-PIF, France

Tutorials and/or group projects following
Netlogo Arnaud Banos | Nathalie Corson | Jeremy Fiegel | Sebastian Grauwin |Nicolas Marilleau | Clara Schmitt
GEPHI Julian Bilcke | David Chavalarias
Open Mole Mathieu Leclaire | Romain Reuillon

Applying to the Summer School

The application tuition rate is €500 for the whole school. Tuition rate includes:

• attendance to all courses
• housing in Paris at the Cité Internationale Universitaire de Paris
• lunches and coffee breaks
• transport tickets in Paris during school days

Important:

From the first announcement day until the registration deadline (31 May), each application will be studied as soon as we receive it (first-come, first-served). If the applicant is selected, a registration confirmation will be quickly sent. We expect each selected applicant to confirm its registration in the week after reception of our email - and to pay the school fees when the dedicated web site will be open (15 May).

Why these rules? Because the school is organized for 25 people only, due to the importance of group projects during this summer school (50% of the total time). Moreover, the sooner you are confirmed, the sooner you can book your flight tickets!

Overview of important dates:

• Application deadline: May 31
• Notification of acceptance of applications: after reception of each application (first-come, first-served)
• Payment website opening: May 15

WE STRONGLY RECOMMEND YOU TO APPLY AS SOON AS YOU CAN (the school is limited to 25!).

 GO TO THE APPLICATION FORM

Final Geospatial Revolution Episode

Over the last few months the Geospatial Revolution Project from Penn State has created some great short documentaries about the use of GIS in our daily lives.

To quote from the site:

"The mission of the Geospatial Revolution Project is to expand public knowledge about the history, applications, related privacy and legal issues, and the potential future of location-based technologies"

The final episode focuses on monitoring global climate change, preventing famine, tracking disease and mapping communities never before seen on a map.

The other three episodes are:

1. The introduction of the geospatial revolution
2. Explore local governments and business use geospatial technology
3. Explores geospatial technology in the world of security
   

If you not seen any of these, they really are worth checking out.

Using agents to explore traffic: Part Two-Micro to Macro

Following on from a previous post on traffic modeling with agent-based models, I have been thinking of other work in this area and came across the following movies on Youtube. The first is a traffic simulator from Martin Treiber. What is interesting is the "coffeemeter" that gives an impression of the accelerations and jerks in the traffic. You can investigate this model further here: http://www.traffic-simulation.de/ or watch the movie below.

The question you might be asking in yourselves is, do such models work in reality? The mathematical theory behind these so-called "shockwave" jams was developed more than 15 years ago using models that show jams appear from nowhere on roads carrying their maximum capacity of free-flowing traffic – typically triggered by a single driver slowing down. Below is a movie of the NetLogo Traffic Basic Model exploring this principle.

Hopefully the movie above helps add something to your question. But if not check out the next movie (make sure the sound is on). In which a team of Japanese researchers recreated the phenomenon on a test-track by putting 22 vehicles on a 230-meter single-lane circuit. Drivers were asked to cruise steadily at 30 kilometers per hour, and at first the traffic moved freely. But small fluctuations soon appeared in distances between cars, breaking down the free flow, until finally a cluster of several vehicles was forced to stop completely for a moment. That cluster spread backwards through the traffic like a shockwave. Every time a vehicle at the front of the cluster was able to escape at up to 40 km/h, another vehicle joined the back of the jam. The full article can be read in New Scientist (click here).

Moving away from traffic jams, as the previous post highlighted we can also use agent-based models to look at traffic intersections. The movie shows a more complicated intersection than in the last post and shows how different intersections can be visualized and modeled.

But while the above movie is rather simplistic, agent-based models can be developed from such simple situations to more complex one. For example, if you can model one type of intersection what is stopping you for modeling more? The movie below shows a more complex set of intersections using Paramics (however, this is noted to be a microsimulation model, if you are interested in finding out the difference between microsimulation and ABM see here).

From a local scene we can also turn to exploring more larger scenes such as entire metropolitan regions. The movie below is of that of TRANSIMS microsimulation-agent based model applied to downtown Chicago:

What I find so interesting about such traffic models is how one can go from basic models at the micro level and scale up such models (and of adding more complexity) to explore more macro phenomena such as traffic jams at metropolitan scales.

Using agents to explore traffic

After spending time in the US, I am amazed how much one has to drive and this got me thinking about using agent-based models for traffic simulations (which is a large body of literature accompanying it). It also relates to my interests in urban systems and the fact that as cities have grown, transportation technologies have evolved (from walking, to trains etc), and now the automobile has become the dominant mode of transport for moving within and between cities. Trips range from journeys to work to shopping trips. The wide spread adoption and use of automobile is also one of the contributors to sprawl (in its many shapes and forms) as the car is not restrained by frequent stops or set routes, for instance such as trains are. Thus, if one can understand the relationships between land use and transportation one can investigate issues relating to urban sustainability. This is where agent-based models come in, in the sense they allow one to focus on the behavior of people. For example, how people decide to go to work.

ABM also allows us to explore simple thought experiments and how more aggregate results emerge from individual interactions such as: what is more effective, a four way stop or a traffic lights at a road intersection? The simple agent-based model presented below utilizes MASON and was created by Omar Guerrero of the CSS department at GMU. The rules of the model are simple, in the sense that at a four way stop, the vehicle that is first to arrive, it is first to move, unless two vehicles arrive at the intersection at the same time and then the vehicle has to give way to the car on the right. While at traffic lights vehicles must stop at red lights. The movie below shows part of the graphical user interface for a particular model run of both a four way stop and traffic light.

Even though this is a simple model, one can explore a number of issues such as how these different intersection configurations impact on the flow of traffic under different volumes of traffic. For example, at low traffic volumes in general, the stop sign is more effective (i.e. allows more cars to cross) than the traffic light. However, at greater traffic volumes the traffic lights out performs the four way stop (in the sense there are more cars in queues) but also with high traffic volumes, one can see oscillations in traffic waiting at the lights while the four way stops create long queues of traffic as shown in the figure below:

Moving away from micro patterns of traffic flows one can use ABM to explore daily commuting. For example, traffic models such as TRANSIMS or MATSim allow for the study of entire metropolitan regions and how traffic jams etc. form. To give a simple example of such a movement, the model presented below illustrates how many individuals can cause traffic jams. The model (using GeoMason) is based on commuters working within the Tyson’s Corner area of Virginia which boarders Washington DC. We take road and travel to work data from the US census and use this as the basis for our model.

The road data acts as a basis for our agents (red) to move from their homes (areas shaded green) to Tyson’s corner and the census data provides us with the number of agents who travel to the area on a daily basis. The agents attempt to find the shortest path from their home to the destination with preferential attachment to highways and freeways over smaller country roads. By running the model, cars start at homes and travel towards Tyson’s Corner and as more cars join certain sections of roads, traffic jams start to form (as speed is a function of the number of cars on a specific section of road). For example in the movie above, individual cars can be distinguished when they are not clustered but when traffic density increases, larger clusters develop.