From Santa Fe Institute Events Wiki

Stochasticity and Space Project

Things we Need:

  • Explicit hypotheses
  • links to papers,
  • state variables
  • definitions of agent traits w.r.t. space variables,
  • forcing conditions
  • sample code?

Looks like we can do anything on a square grid in NetLogo, and even import GIS data.


State variables:

  • Limiting resource (which can also be in excess)(E.g., water, nutrients)
  • Patch/cell/region ability to conserve resource (E.g., soil organic matter)
  • Patch connections (e.g., elevation -> horizontal flow)
  • Connectivity (i.e. how well patches are connected)

Agent characteristics:

  • Efficiency in capturing resource
  • Efficiency in surviving low-resource conditions
  • R-k strategy
  • Spatial reach, for getting resource or spreading offspring
  • Interactions? One kind of agent more efficient in the presence of another?
  • Threshold responses to external inputs, or saturation
  • What ecological processes does an agent do? (e.g. growth, water uptake, nutrient uptake, death, dispersal etc.)

Forcing conditions:

  • Input of resource, variable in space or time
  • Variance of input


  • Variable resource input favors different agent traits than reliable inputs with the same mean value
  • Agents develop spatial variability to gather sparse resources
  • Unreliable resources favor cooperative strategies (Demetrius, e.g.)
  • Hubler's hypotheses: with little noise, the system minimizes dissipation and is efficient; with much noise, the system maximizes dissipation and is robust.



maybe we need emails to facilitate communications.

  • Xiaoli:
  • Xue:
  • Χλοε: chlewis (at berkeley edu)

we are looking for the unknown X in Xeriscapes.