Table 2. Exponents β(r) and β(σ) as in and , which characterize the mean degree growth rate r and the standard deviation σ in the evolution of the model network and the empirical networks (Flickr before Epinions in the parentheses). The parameters are the same as in Fig. 3 and Fig. 4.

	kf	ks	kp
β(r)	0.0 (0.0 & 0.0)	0.05 (0.10 & 0.0)	0.0 (0.0 & 0.0)
β(σ)	0.25 (0.18 & 0.21)	0.28 (0.23 & 0.18)	0.5 (0.17 & 0.2)