Table 1.
Sender and donor strategies in the Sir Philip Sidney Game.
Fig 1.
Size of basin of attraction for handicap signaling.
Simulation results from a random sample of instances of the Sir Philip Sidney game where the parameters satisfy the conditions necessary for conflict of interest and the existence of the signaling equilibrium. (a) shows the probability that a randomly chosen initial population evolves to the signaling equilibrium. (b) illustrates the relationship between the probability of evolving signaling and the underlying cost of the signal.
Fig 2.
Phase portrait of hybrid equilibrium.
From [27]. This illustrates the phase portrait of the two population replicator dynamics on the plane comprised by the four hybrid equilibrium strategies. The child strategies are signal only when needy (S2) and always signal (S4), and the parent strategies are transfer only if the signal is observed (R2) and never transfer (R3).
Fig 3.
Size of basin of attraction for hybrid equilibrium.
Simulation results for a random sample of instances of the Sir Philip Sidney game where the parameters satisfy conflict of interest and the conditions necessary for the existence of the hybrid equilibrium. (a) shows the probability that a randomly chosen initial population evolves to the hybrid equilibrium. (b) illustrates the relationship between the probability of evolving to the hybrid equilibrium and the underlying cost of the signal.
Fig 4.
Illustration of the two hybrid equilibria in the Sir Philip Sidney game with two signals.
Solid lines represent play with probability 1, dotted lines represent play with non-unity, positive probabilities. The lines on the left represent the strategies of the child, while lines on the right illustrate the strategy of the parent. (a) represents a version of the hybrid equilibria most closely related to the one found in [27]. (b) represents a new hybrid equilibrium which is discussed in more detail in the Appendix.
Fig 5.
A simplex indicating the probability of evolving to the handicap-signaling equilibrium, hybrid equilibrium, or some other outcome in a randomly chosen Sir Philip Sidney game.
Each point represents one random setting of the parameter values. Its location in the simplex indicates the size of the basin of attraction for the various outcomes. The size of the basin of attraction is inversely proportional to its distance from the vertex. For example, if the point is close to the lower right vertex, this indicates that the basin of attraction for the hybrid equilibrium is significantly larger than for the other two outcomes.
Fig 6.
The relationship between the size of the basins of attraction and the two cost parameters.
Blue x’s represent the size of the basin of attraction of the hybrid equilibrium, black crosses represent the size of the basin of attraction of the handicap-signaling equilibrium. The plot on the left displays the relationship between the size of the basins of attraction and the cost of the low cost signal, cl. The plot on the right shows the relationship between the size of the basins of attraction and the cost of the high cost signal, ch.