Glen wrote: > No. Adjusting a rule is entirely different from adjusting a number. > The adjustment of a number merely explores a space. A number spectrum > does specify/describe a metric. So, for example, adjusting an integer > with particular boundaries for the model, say [-10, 100] provides a > well-defined space. For a fixed instruction set there's a fixed set of programs that can be encoded in a fixed sized vector. The behaviors that such a program can exhibit are also entirely fixed given precise initial state. General and effective methods for global search can in fact be exactly the same for numbers and rules: 0) create a set of starting candidates 1) evaluate them, 2) tweak the good 3) destroy the bad, 4) go to 1.
To have good optimizations for searching number spaces (more efficient than exhaustive grid search), then additional assumptions need to be made, such as that the numbers come from a differentiable function or have systematic gradients. For that matter [-10, 100] is not a well defined space for a model because there are no units, and no given meaning to how that range ought to relate to sensitivities in other agents. An agent model is an assembly. If a component of the assembly is tweaked a bit, that doesn't justify calling it a whole new model any more than if a few parameters in the model changed a bit. It is a versioning issue. Marcus ============================================================ FRIAM Applied Complexity Group listserv Meets Fridays 9a-11:30 at cafe at St. John's College lectures, archives, unsubscribe, maps at http://www.friam.org
