http://friam.383.s1.nabble.com/Nature-Ball-reviews-Miller-Page-and-Epstein-tp524386p524396.html
"the observed statistics....can be derived". Indeed.
>
>
> On 8/9/07, *Marcus G. Daniels* <marcus at snoutfarm.com
> <mailto:marcus at snoutfarm.com>> wrote:
>
> Right, "generative social science", a.k.a. "made up stuff"...
>
>
> Speaking of which, for those in the vicinity of Los Alamos:
>
> Thursday, August 9th,2007
>
> 4:00 pm - 5:00 pm
>
> CNLS Conference Room (TA-3, Bldg 1690)
>
> Gang Recruitment and Growth: A Cellular Automata and Directed Graph Approach to
> the Statistics of Gang Sizes
>
>
> William I. Newman
> UCLA
>
> Cellular automata models can be developed to describe the evolution of emergent
> dynamical systems that maintain a discrete character, including those with an
> implicit hierarchical character. Moreover, these models can be related to
>
> directed graphs. These methods have found widespread application in condensed
> matter physics (e.g., diffusion limited aggregation and crystal growth,
> sandpiles andself-organized criticality) as well as in earth and environmental
>
> physics (e.g., models of earthquakes and river networks). In particular, models
> developed for forest fires are manifestly complex systems that show
> well-preserved scaling laws relating to the frequency of forest fires relative
>
> to their size. In sociological studies of conflict and deadly quarrels, similar
> statistical scaling laws have been observed, e.g., Richardson, with identical
> power-law indices. In earlier work, Gabrielov, Newman, and Turcotte (199?)
>
> succeeded in deriving from first principles those scaling laws. Here, we show
> that a simple redefinition of terms makes it possible for the statistics of
> gangs to be obtained from these other cellular automata models. In particular,
>
> by equivalencing the recruitment of gang members in the sociological problem
> with the planting of trees in the environmental problem, the observed
> statistics of gang populations and their prevalence can be derived.
>
>
> LANL Host: Mac Hyman, T-7
>
>
>
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