Title
Semi-Blind Inference of Topologies and Dynamical Processes over Graphs.
Abstract
Network science provides valuable insights across numerous disciplines including sociology, biology, neuroscience and engineering. A task of major practical importance in these application domains is inferring the network structure from noisy observations at a subset of nodes. Available methods for topology inference typically assume that the process over the network is observed at all nodes. However, application-specific constraints may prevent acquiring network-wide observations. Alleviating the limited flexibility of existing approaches, this work advocates structural models for graph processes and develops novel algorithms for joint inference of the network topology and processes from partial nodal observations. Structural equation models (SEMs) and structural vector autoregressive models (SVARMs) have well-documented merits in identifying even directed topologies of complex graphs; while SEMs capture contemporaneous causal dependencies among nodes, SVARMs further account for time-lagged influences. This paper develops algorithms that iterate between inferring directed graphs that best fit the data, and estimating the network processes at reduced computational complexity by leveraging tools related to Kalman smoothing. To further accommodate delay-sensitive applications, an online joint inference approach is put forth that even tracks time-evolving topologies. Furthermore, conditions for identifying the network topology given partial observations are specified. It is proved that the required number of observations for unique identification reduces significantly when the network structure is sparse. Numerical tests with synthetic as well as real datasets corroborate the effectiveness of the novel approach.
Year
Venue
Field
2018
arXiv: Learning
Network science,Autoregressive model,Mathematical optimization,Inference,Directed graph,Network topology,Theoretical computer science,Solver,Iterated function,Mathematics,Computational complexity theory
DocType
Volume
Citations 
Journal
abs/1805.06095
2
PageRank 
References 
Authors
0.37
11
3
Name
Order
Citations
PageRank
Vassilis N. Ioannidis1147.34
Yanning Shen2789.32
G. B. Giannakis3114641206.47