Title
The degree distribution of the generalized duplication model
Abstract
We study and generalize the duplication model of Pastor-Satorras et al. [Evolving protein interaction networks through gene duplication, J. Theor. Biol. 222 (2003) 199-210]. This model generates a graph by iteratively "duplicating" a randomly chosen node as follows: we start at t0 with a fixed graph G(t0) of size t0. At each step t t0 a new node vt is added. The node vt selects an existing node u from V(G(t - 1)) = {v1,...,vt-1} uniformly at random (uar). The node vt then connects to each neighbor of the node u in G(t - 1) independently with probability p. Additionally, vt connects uar to every node of V(G(t - 1)) independently with probability r/t, and parallel edges are merged. Unlike other copy-based models, the degree of the node vt in this model is not fixed in advance; rather it depends strongly on the degree of the original node u it selected. Our main contributions are as follows: we show that (1) the duplication model of Pastor-Satorras et al. does not generate a truncated power-law degree distribution as stated in Pastor-Satorras et al. [Evolving protein interaction networks through gene duplication, J. Theor. Biol. 222 (2003) 199-210]. (2) The special case where r = 0 does not give a power-law degree distribution as stated in Chung et al. [Duplication models for biological networks, J. Comput. Biol. 10 (2003) 677-687]. (3) We generalize the Pastor-Satorras et al. duplication process to ensure (if required) that the minimum degree of all vertices is positive. We prove that this generalized model has a power-law degree distribution.
Year
DOI
Venue
2006
10.1016/j.tcs.2006.08.045
Theor. Comput. Sci.
Keywords
DocType
Volume
node u,node vt,generalized duplication model,J. Theor,duplication model,power law,computational proteomics,Evolving protein interaction network,existing node u,random graph generation,power-law degree distribution,original node u,new node vt,gene duplication
Journal
369
Issue
ISSN
Citations 
1
Theoretical Computer Science
19
PageRank 
References 
Authors
1.52
20
6
Name
Order
Citations
PageRank
G. Bebek1191.52
petra berenbrink21026.53
Colin Cooper328730.73
T. Friedetzky4191.52
Joseph H. Nadeau514921.83
S. C. Sahinalp6211.91