Table 1 Trend test between time average density of signals 〈ρσt, and normalized apparent cost \(\bar{c}\), and between 〈ρσt and time average payoff of signals \({\langle {w}_{\sigma }^{a}\rangle }_{t}\) in different games. From top to down, Spearman’s rank correlation coefficient between 〈ρσt and \(\bar{c}\), and between 〈ρσt and \({\langle {w}_{\sigma }^{a}\rangle }_{t}\), p value of the Spearman test between 〈ρσt and \(\bar{c}\), and between 〈ρσt and \({\langle {w}_{\sigma }^{a}\rangle }_{t}\), and finally, p value of the Mann-Kendall test between 〈ρσt and \(\bar{c}\), and between 〈ρσt and \({\langle {w}_{\sigma }^{a}\rangle }_{t}\). Here, an average over a window of length 5000 time steps is taken. In all the cases both tests strongly support a trend between payoff and density of signals, but in the case of TTD and SD, fail to establish a trend between the apparent cost and density of signals. In all the cases, the trend between density and fitness is significantly stronger compared to the trend between apparent cost and density.

From: Evolution of costly signaling and partial cooperation

n

PD

TTD

SD

BS

leader

\(r({\bar{c}}_{\sigma },{\langle {\rho }_{\sigma }\rangle }_{t})\)

−0.46

−0.13

−0.37

−0.52

−0.59

\(r({\langle {w}_{\sigma }^{a}\rangle }_{t},{\langle {\rho }_{\sigma }\rangle }_{t})\)

0.93

0.97

0.92

0.96

0.96

\({p}_{r}({\bar{c}}_{\sigma },{\langle {\rho }_{\sigma }\rangle }_{t})\)

3.7 × 10−2

5.7 × 10−1

1.0 × 10−1

1.6 × 10−2

5.8 × 10−3

\({p}_{r}({\langle {w}_{\sigma }^{a}\rangle }_{t},{\langle {\rho }_{\sigma }\rangle }_{t})\)

2.2 × 10−9

6.7 × 10−13

5.5 × 10−9

8.6 × 10−12

3.8 × 10−12

\({p}_{MK}({\bar{c}}_{\sigma },{\langle {\rho }_{\sigma }\rangle }_{t})\)

4.7 × 10−2

3.4 × 10−1

1.2 × 10−1

2.1 × 10−2

1.2 × 10−2

\({p}_{MK}({\langle {w}_{\sigma }^{a}\rangle }_{t},{\langle {\rho }_{\sigma }\rangle }_{t})\)

6.9 × 10−7

4.1 × 10−8

9.6 × 10−7

1.7 × 10−7

6.0 × 10−8