Figure 3

Superlinear relation in the fitness model. Solid lines denote the theoretical values indicated by Eq. (2), while symbols represent the corresponding simulation results (average of 500 runs). Scaling relation \(M\propto N^{\beta}\) with \(1 < \beta < 2\) emerges by varying \(N_{\mathrm { P}}\) when \(N_{\mathrm { P}}\) is small (approximately \(20 \leq N_{\mathrm { P}}\leq 300\)). Inset: increasing \(N_{\mathrm { P}}\) to 10,000 restores quadratic scaling \(M\propto N^{2}\) since \(q_{0}\approx 0\) and thereby the finite-size effect disappears