The CA

This is the "Majority" cellular automaton model. You can think of it as a model of peer pressure. The rules are that each cell tries to do what the majority of its neighbors (peers) are doing.

If we have n states, labelled 0 through n-1, each site looks at some set of neighbors. It then sets its own state to whatever the majority of its neighbors are doing.

The Controls

See the parent web page for general controls.

Controls specific to this particular applet are:

• Number of states: You can change the number of states allowed per cell, by typing in a number and then either hitting "Enter" or clicking on the "Set numStates" button.
• Nbor method: method for deciding which neighbors to examine.
  • Random: If set to "Random", each site randomly chooses one of its neighbors to look at, and sets its own state to the same as that of its neighbor.
  • All: If nbor method is set to All, then each site looks at all of the sites in its neighborhood, and then sets its own state to whichever state is most common in the neighborhood. If it's a tie, i.e. multiple states are tied for first place, then the target site chooses one of the tied majority states, at random.
• Nhood size: size of the neighborhood to use.
  • vonNeumann: Each site only looks at its four adjacent neighbors (north, south, east and west).
  • Fixed radius: if the radius is set to r, the neighborhood of a site is all sites within plus or minus r units, horizontally and vertically. So r=1 corresponds to a 3x3 block of sites (often called the Moore neighborhod). r=2 corresponds to a 5x5 block of sites. And in general, a given value of r corresponds to a (2r+1)x(2r+1) block of sites.