Glossary: Difference between revisions

For finite populations time is simulated in units of Monte-Carlo steps (MC steps). If the population size is <math>N</math>, then a single MC step consists of <math>N</math> individual player actions.

A player who acts may [[#Imitation|imitate]] a neighbor, they may [[#Reproduction|reproduce]] (prompting a neighbor to die to make room for the offspring), they may [[Parameters/Population#Moran process (death-birth)|die]] (prompting a neighboring player to reproduce to replace them), all of which may change someone's game [[#Game|strategy]] and [[#Game|payoffs]].  Which of these actions occur, and in what order, is governed primarily by the [[Parameters/Population#Population update|population update settings]].

If you wish to model that interactions occur only a few times per player per MC time step, then use parameter nInteractions to indicate the number of interactions.  For instance, if each player has four interaction neighbors, and nInteractions was 3 (or 7), then an action would play games with a randomly chosen 3 (or 7) of the four neighbors, with replacement, and the scores accumulated or averaged.  Note that the chosen neighbors' scores will change too, since their scores reflect the additional games played.

If you wish to model per-player interactions as very frequent vis à vis the MC time step, you can set the parameters so that whenever a vertex's traits change (via mutation, imitation, or death and replacement by someone else's offspring), the new player plays games with all their neighbors to arrive at the limiting case, as if nInteractions was infinite with averaged scores.  Neighbors scores are also adjusted to reflect their score accounting for the change in their neighborhood.