Table 1

Meaning of symbols
Symbol Meaning
M Number of groups
θ Probability that a donor and recipient in a one-shot game are in the same group
r∈{G, B}M Reputation vector of a player in the eyes of M observers
pk(r) Probability that a player in group k has reputation vector r
pk(r) Probability that a player outside group k has reputation vector r
σ(r)∈{C, D} Donor’s action to a recipient having reputation r∈{G, B}
Φr(a,r) Probability that an observer assigns reputation r∈{G, B} to a donor selecting action a∈{C, D} to a recipient having reputation r∈{C, D}
pin(r) Probability that a player in the eyes of an ingroup observer has reputation r
pout(r) Probability that a player in the eyes of an outgroup observer has reputation r

Nakamura and Masuda

Nakamura and Masuda BMC Evolutionary Biology 2012 12:213   doi:10.1186/1471-2148-12-213

Open Data