Edmund,
We have been experimenting with agent-based models in which we use AI techniques - learning classifier systems - that allow agents to learn by experience and alter their behavior in response. We apply our models to the Maine lobster fishery which we know with some intimacy. Our interest is in the factors affecting the formation of social structure (for which the fishery, unlike most others, is well known) and in the collective efficiency of search. The model nicely fits the important patterns in the fishery. Our confidence in the model is based on our familiarity with the social processes in the fishery and also on some very unusual, very fine scale data provided by 44 fishermen. The results are not, as Eliot mentions, proof by any means, but the model does allow us to explore the factors that affect social structure and collective efficiency. These explorations lead us to emphasize the importance of the cost of information about the location of valuable resources, which is perhaps not surprising in a fishery, but it is something which standard bioeconomics does not consider. There are (at least) two important things we’ve learned that may be of value to the ABM community: The first is a methodology that incorporates agent learning and adaptation. The second is the ability to give an operational definition to the idea of costly information/knowledge. The latter is very important in a fishery, but also in almost any walk of life.
I’ve attached a short ‘PR’ description of the model. Two papers we’ve recently published are:
Wilson, J., et al. 2013. Costly information and the evolution of self-organization in a small, complex economy. Journal of Economic Behavior and Organization, vol. 90, p. S76-S93. doi:10.1016/j.jebo.2012.12.019
Wilson, J.; Acheson, J.; Johnson, T. 2013. The cost of useful knowledge and collective action in three fisheries. Ecological Economics. doi: 10.1016/j.ecolecon.2013.09.012
Yours,
Jim Wilson
Professor of Marine Sciences and Economics
School of Marine Sciences
University of Maine
207-581-4368 (office)
207-991-4368 (cell)
On Jan 2, 2014, at 5:57 PM, Rich, Eliot <[log in to unmask]> wrote:
> Dear Sylvie (and list members)
>
> Thank you for the reference to your paper.
>
> I have a continuing interest in how simulation scientists validate (gain strength and confidence in) and verify (demonstrate correctness) models, so please forgive me for inserting a possibly contentious statement about the premise of proof. Proof of a theory is different than demonstrating a "clear and deliberate relationship" as described in Edmund's post. In mathematics, we can construct proofs by bounding the rules and logics acceptable for our problem. Unlike mathematics, social simulators do not have the tools or logics needed to ensure provability in our chosen reality.
>
> Models, whether ABM or others, simulate properties that exist only in reality. When a simulation provides evidence that supports a theory, it can help us learn about the theory's strengths and its applicability to problems, but it does not prove that our simulation is correct. Nor can it, unless we believe we are exactly replicating the processes that happen in society.
>
> In my own work in dynamic simulation, we attempt to disprove theory through simulation, rather than prove it. I argue that the application of simulation to Reductio ad absurdum is an important and valid application of our craft. But still, it's not proof.
>
> A wonderful statement of the concern was provided by Oreskes, N. et al., "Verification, validation, and confirmation of numerical models in the earth sciences". Science February 4, 1994, pp 641-646.
>
> What do you (and others) think? Does Proof vs. "Clear and Deliberate Relationship" matter?
>
> Best,
>
> Eliot
>
> Eliot Rich
> Associate Professor
> Department of Information Technology Management School of Business University at Albany State University of NY, USA
>
> [log in to unmask]
>
> -----Original Message-----
> From: News and discussion about computer simulation in the social sciences [mailto:[log in to unmask]] On Behalf Of Huet Sylvie
> Sent: Thursday, January 02, 2014 12:59
> To: [log in to unmask]
> Subject: Re: [SIMSOC] ABM To Test Theory ...
>
> I would say the Leviathan model starting from the Hobbes hypothesis on the individual dynamics, and not only since I have participated to this work (or at least I think so). That is a very innovative work proving the emergence of various leaderships (as the Leviathan one). It is based on a coupled individual dynamics of vanity and opinion propagation through gossip. It shows each one self-esteem is built through individual interactions which in turns lead to different organisations of people in terms of relations. These organisations can be usefully compared to various power structure forms. This is a recent work. It is continuing and promises a lot in terms of understanding. However, the first published paper cited below has already proved the interest of the individual-based model.
>
> The Leviathan Model: Absolute Dominance, Generalised Distrust, Small Worlds and Other Patterns Emerging from Combining Vanity with Opinion Propagation. Guillaume Deffuant, Timoteo Carletti and Sylvie Huet (2013). Journal of Artificial Societies and Social Simulation 16 (1) 5. <http://jasss.soc.surrey.ac.uk/16/1/5.html>
>
> Sylvie Huet
> Laboratoire d'Ingénierie pour les Systèmes Complexes (LISC) IRSTEA
> CS20085
> 9 avenue Blaise Pascal
> Campus des Cézeaux
> 63178 AUBIERE CEDEX - France
> Tél. (33) (0)4.73.44.06.15
> http://motive.cemagref.fr/people/sylvie.huet
>
>
> -----Message d'origine-----
> De : News and discussion about computer simulation in the social sciences [mailto:[log in to unmask]] De la part de Edmund Chattoe-Brown Envoyé : jeudi 2 janvier 2014 16:52 À : [log in to unmask] Objet : [SIMSOC] ABM To Test Theory ...
>
> Dear All,
>
> What would you say are the best/most thought provoking/most persuasive attempts to test or build on existing theory using ABM? By this I mean not just _any_ ABM (which could be argued in a general sense to build
> theory) but one that has some clear and deliberate relationship with a reasonably well known piece of published theory (like labelling theory, Marxism, the Hobbesian state of nature, Friedman's claim that profit making firms will drive out non profit making firms, the theory of Habermasian communicative action and so on.)
>
> I'll summarise back to the list.
>
> Happy 2014,
>
> Edmund
>
> --
> Edmund Chattoe-Brown
> [log in to unmask]
>
> --
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