Piecewise Stationary Modeling of Random Processes Over Graphs With an Application to Traffic Prediction

Abstract

Stationarity is a key assumption in many statistical models for random processes. With recent developments in the field of graph signal processing, the conventional notion of widesense stationarity has been extended to random processes defined on the vertices of graphs. It has been shown that well-known spectral graph kernel methods assume that the underlying random process over a graph is stationary. While many approaches have been proposed, both in machine learning and signal processing literature, to model stationary random processes over graphs, they are too restrictive to characterize real-world datasets as most of them are non-stationary processes. In this paper, to wellcharacterize a non-stationary process over graph, we propose a novel model and a computationally efficient algorithm that partitions a large graph into disjoint clusters such that the process is stationary on each of the clusters but independent across clusters. We evaluate our model for traffic prediction on a large-scale dataset of fine-grained highway travel times in the Dallas-Fort Worth area. The accuracy of our method is very close to the state-of-the-art graph based deep learning methods while the computational complexity of our model is substantially smaller.

Graph Signal Sampling Under Stochastic Priors

“…This property is also used in [63], [64]. Note that Γ x is diagonalizable by U if and only if (20) is satisfied [65].…”

Construction and Analysis of Queuing and Reliability Models Using Random Graphs

“…Apparently, the most striking continuation of them are works on modelling of random growing networks [7]. As applications of random processes on graphs, along with lattice physical models, we can now specify the questions of traffic prediction [8], machine learning [9], contact processes on graphs [10], computational biology [11] and etc.…”