Please accept the organisers' apologies if you receive multipl copies of this DEADLINE EXTENSION.

M2M2
Second "Model to Model" workshop:
Comparing and combining agent-based models with each other,  
and with other models  
Workshop to be held on 14 and 15 September 2004, Valladolid, Spain
In association with the second ESSA conference

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FURTHER DEADLINE EXTENSION: NEW DEADLINE 24 May 2004
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NOTE: All those who have already submitted papers are welcome to submit updated versions
by the new deadline. Please accept the organisers' apologies for the delay in reviewing
your papers due to the deadline extension.

Aims and Topic

In recent years there has been an explosion of published literature utilising Multi-
Agent-Based Simulation (MABS) to study social, biological and artificial systems. 
However, despite the plethora of novel models and interesting results it is rare that 
models are compared, built-on or transferred between researchers. It would seem 
there is a dearth of  "model-to-model" analysis. 
The second M2M workshop, M2M2, is aimed at gathering researchers in MABS who 
are interested in understanding and furthering the transferability of knowledge 
between Multi-Agent Based Simulation models and beyond. As in the first M2M 
workshop (Marseille, France, March-April 2003), papers are invited reporting 
comparisons and validations involving two or more models, at least one being an 
agent-based model. 
Understanding complex systems often seems to necessitate the use of more than one 
model.  By specifically comparing models a better view of what modelling brings to 
the understanding of (real and artificial) societies may be facilitated. The union of two 
or more models with apparently incompatible levels of abstraction, comparisons of 
results from related studies, and the description of model findings in ways allowing 
others to check and replicate them, all require the development of methods that 
improve rigor and reproducibility.
Approaches of interest include but are not limited to: 
*       Rewriting models that others have described in papers so as to understand 
them more deeply and reproduce the stated results;
*       Composition of models where different scales are inter-related in a larger 
model - the results of one model being used in the other; 
*       Aligning of models: a comparison of different models that announce the same 
type of results, so as to evaluate their actual similarities;
*       Comparison of different models based on their fitness to a set of data, 
accumulated through field studies or experiments; 
*       Using one model as a post-hoc summary or abstraction of another model's 
results; Constraining the scope of an existing model to enable more powerful 
techniques to be applied in a different computational framework; 
*       Using models with different structures and assumptions to confirm each 
other's results; 
*       Determining what to do when two models give results that contradict each 
other. 
*       Constructing and using taxonomies or description schemas for use in 
comparing or combining MABS models.

At the first M2M workshop, two specific issues were addressed: 
(1) How can different multi-agent models best be compared? (What kinds of 
comparison are feasible, and how can comparisons be useful?) 
(2) Is it possible to transmit the structure of a model and its results among researchers 
through papers, or should we look for other means of transmission? 

The meeting proved that the issues at stake seemed fundamental for many 
practitioners. Most papers addressed the replication of models through alignment: 
comparing different level of aggregation describing the same system and evaluating 
the differences and similarities between centralised models and distributed ones; 
checking the influence of rationality at different result levels, or trying to integrate 
several forms of rationality. Other papers addressed the issue of replication and 
concluded here that there are considerable conceptual and practical difficulties in 
replicating others' work, but doing so can be most enlightening. 

A number of papers have been published in a resulting special issue in
JASSS (http://jasss.soc.surrey.ac.uk/6/4/5.html). Authors wishing to
submit a paper to M2M2 are advised to refer to this issue,  although
it is not representative of all possible approaches on the
topic. Following M2M, this new workshop will hopefully bring together
an international community and produce new frameworks to look at
agent-based simulation results. 

Date and Venue

The M2M2 workshop will be held in association with the 2004 ESSA conference, as a 
1 1/2 day workshop on the 14th and 15th of September 2004 in Valladolid, Spain. 
The same format will be kept for presentation, 45 minutes being given to each 
participant to present their paper.

Call for Papers

Send paper by email by May 1, to:
     Nick Gotts ([log in to unmask]) or 
     Guillaume Deffuant ([log in to unmask]). 
Papers should be sized between 10 and 20 pages and will be selected through peer 
review. Contributors wishing to submit demos, models, or other material with their 
paper are invited to contact a member of the organising committee.

Organising committee

Claudio Cioffi-Revilla
Guillaume Deffuant
Nick Gotts
Juliette Rouchier

Local organisation

 Cesareo Hernandez Iglesias

Program committee (to be confirmed)
Rob Axtell, Francois Bousquet, Paul Davidsson, Marco Janssen, Christophe Le Page, 
Scott Moss, Mario Paolucci, Javier Pajares, Adolfo Lopez, David Hales, Bruce 
Edmonds,  Frederic Amblard, Bill McKelvey, Luis Antunes, Olivier Barreteau, Matt 
Hare, Thierry Faure, Thomas Brenner, Wander Jager, Catholijn Jonker. 


Nicholas M. Gotts
The Macaulay Institute, Aberdeen AB15 8QH
Scotland, UK
Tel: +44 (0)1224 498200 ext. 2229
Fax: +44 (0)1224 311556
e-mail: [log in to unmask]
http://www.macaulay.ac.uk/fearlus