Evolving Networks Created by Preferential Attachment and Decay
Justin Downes
TL;DR
The paper tackles preserving a scale-free, power-law degree distribution in evolving networks where edges can be added and removed over time. It proposes a unified Evolution Model that couples standard preferential attachment with edge turnover, employing inverted deletion probabilities to counteract excessive growth of high-degree nodes, and applies it across three PA-based base models: Barabási-Albert, Bianconi-Barabási, and the Relevance model. In simulations with 10,000 nodes and 300 evolution steps (adding/removing ~1,000 edges per step), the BB model generally best maintains the power-law, while BA tends toward a normal-like distribution and Relevance can strengthen the heavy tail under certain decay conditions, though limits arise from decay. The work provides a practical, simulation-based framework for generating and evaluating dynamic, scale-free networks and offers directions for analytic treatment and agent-based extensions.
Abstract
Growing synthetic networks that follow power law distributions of a node's degree often involves adding one node at a time. Each node is added to the network with a fixed amount of edges and those edges are frozen for all future time steps. Yet real world networks often continuously evolve with edges being added and removed while new nodes are added to the network. Many existing growth models based on preferential attachment do not account for this evolutionary capability and when you extend their growth methods to add and remove edges to existing nodes the node degree distribution quickly loses its scale-free structure. This paper will go over a method to extend well known preferential attachment growth models to allow for the evolution of edges within a network while still maintaining a power law node degree distribution.
