w | Individual fitness |
r | Relatedness between any two randomly selected individuals in the group |
s | Individual cost to cooperator growth in the group |
k | Number of individuals in a group (an inverse measure of kin selection) |
c | Individual cost to cooperator dispersal |
e | Individual cost to cheater dispersal |
Q | Impact of sedentary cheaters on the individual fitness of group members (via consumption of the public good) |
P | Impact of sedentary cooperators on the individual fitness of group members (via production of the public good) |
n | Relative frequency of cooperators in the group (1-n is the proportion of cheaters) |
z | Relative frequency of cheaters dispersing |
y | Relative frequency of cooperators dispersing |
d | Overall investment in dispersal. d = yn + z(1-n) |
Φ | Overall cooperation with respect to the public good. Φ = n*(1-y*)+(1-n*)z* |
σ | Association between dispersal and cooperation. σ = y/(y+z) |