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Overview

FEARLUS Model 0-3 & 0-5 Parameters

Environment parameters

Horizontal size The number of horizontal cells in the environment grid. (Each cell is a land parcel)
Vertical size The number of vertical cells in the environment grid.
Neighbourhood function The function used to determine the physical neighbourhood of cells in the grid. This can either be Von Neumann, or Moore.
Topology The shape described by the surface of the environment. If the boundaries of the environment are wrapped around (such that cells on the extreme left of the environment have cells on the extreme right as neighbours, and similarly for those at the top and bottom), then the surface is toroidal, otherwise it is planar (referred to as bounded in model0-3).
Maximum year The model can be scheduled to terminate after a specified number of years have been simulated.
Land parcel physical characteristic bitstring size The physical characteristics of each land parcel (which in real life would be such things as gradient or soil type) are represented using a bitstring of this size. These remain constant from year to year, but may vary over the space.
Number of cycles of land parcel physical characteristic clumping CA to use The physical characteristic bitstrings can be clumped using a CA algorithm. This is to create distinct regions in the environment with similar land parcel physical characteristics. This parameter specifies the number of cycles to run the CA for.
Land parcel bitstring file A model run may optionally specify a file from which to load the land parcel bitstrings.
Climate bitstring size The climate is also represented by a bitstring containing this number of bits
Climate toggle probabilities Each bit in the climate has a unique probability of changing value each year. This is used to represent changes in the climate from one year to the next.
Climate bitstring file As an alternative to specifying toggle probabilities, the climate bitstring can be loaded from a file of bitstrings. This is useful for paired replicate runs, in which as many environmental features as possible need to be kept the same.
Economy bitstring size The number of bits to use to represent the economy
Economy toggle probabilities Just as the climate can change from year to year, so too can the economy. Each bit has a specified probability of changing value.
Economy bitstring file The economy bitstrings can also be loaded from a file each year, just as the climate can.
(Land use bitstring size) The land uses are represented by bitstrings too. This parameter is the sum of the land parcel, climate and economy bitstring sizes.
Land use don't care bit bitstring probability The probability of getting a "don't care bit" in the land use bitstring.
Land use bitstring file Land use bitstrings may optionally be loaded from a file.
Number of land uses The number of different land uses that land managers can choose from.

Land Manager Parameters

Break-even threshold The cost deducted from the yield of each land parcel when land managers accumulate wealth from their land.
Land parcel price All land parcels have the same fixed price used when they are transferred between land managers.
Number of subpopulations Land managers may be grouped into subpopulations. Typically, these groupings are based on the decision algorithm the land managers use for selecting land uses.
Subpopulation probability Each subpopulation has a probability that any new land manager created will belong to that subpopulation.
Neighbouring physical characteristic noise Land managers with imitative decision algorithms may find out the physical characteristics of neighbouring land managers' land parcels. This parameter controls the degree of noise applied to the physical characteristics, and is set at the environment level.
Neighbourhood weighting range Each land manager has their own neighbourhood weighting parameter, controlling the amount of attention to pay to information gained from neighbouring managers' land parcels as opposed to that from their own, which is set according to this range. The range is set at the subpopulation level.
Neighbourhood weighting change unit This is an environment level parameter (a legacy from model0-2) that specifies the amount to increase the neighbourhood weighting by for each land parcel a manager has had to sell in a particular year, and the amount to decrease the neighbourhood weighting by for each land parcel bought.
Habit threshold range The range of values land managers in a particular subpopulation may have for their habit threshold. This specifies a threshold of yield from a land parcel at which land managers may be said to be content.
Imitative probability range The range of values land managers in a particular subpopulation may have for their imitative probability.