activity
20142019
most citedAn Efficient Approach to Graphical Modelling of Time Series

24 citations · 60 across the 8 of their papers we have counts for

collaborators

8 papers

math.ST2019

Extending the Davis-Kahan theorem for comparing eigenvectors of two symmetric matrices II: Computation and Applications

J. F. Lutzeyer, A. T. Walden

The extended Davis-Kahan theorem makes use of polynomial matrix transformations to produce bounds at least as tight as the standard Davis-Kahan theorem. The optimization problem of…

stat.ME2017★ 4 cited

Comparing Graph Spectra of Adjacency and Laplacian Matrices

J. F. Lutzeyer, A. T. Walden

Typically, graph structures are represented by one of three different matrices: the adjacency matrix, the unnormalised and the normalised graph Laplacian matrices. The spectral (ei…

math.ST2017

Intrinsic Analysis of the Sample Fréchet Mean and Sample Mean of Complex Wishart Matrices

L. Zhuang, A. T. Walden

We consider two types of averaging of complex covariance matrices, a sample mean (average) and the sample Fréchet mean. We analyse the performance of these quantities as estimators…

stat.ME2016★ 7 cited

A Frequency Domain Test for Propriety of Complex-Valued Vector Time Series

Swati Chandna, Andrew T. Walden

This paper proposes a frequency domain approach to test the hypothesis that a complex-valued vector time series is proper, i.e., for testing whether the vector time series is uncor…

stat.AP2016★ 2 cited

A Sampling Strategy for Projecting to Permutations in the Graph Matching Problem

R. J. Wolstenholme, A. T. Walden

In the context of the graph matching problem we propose a novel method for projecting a matrix , which may be a doubly stochastic matrix, to a permutation matrix We observe…

math.ST2015★ 16 cited

Partial Coherence Estimation via Spectral Matrix Shrinkage under Quadratic Loss

D. Schneider-Luftman, A. T. Walden

Partial coherence is an important quantity derived from spectral or precision matrices and is used in seismology, meteorology, oceanography, neuroscience and elsewhere. If the numb…

stat.AP2015★ 24 cited

An Efficient Approach to Graphical Modelling of Time Series

R. J. Wolstenholme, A. T. Walden

A method for selecting a graphical model for -vector-valued stationary Gaussian time series was recently proposed by Matsuda and uses the Kullback-Leibler divergence measure to…

math.ST2014★ 7 cited

Random Matrix Derived Shrinkage of Spectral Precision Matrices

A. T. Walden, D. Schneider-Luftman

Much research has been carried out on shrinkage methods for real-valued covariance matrices. In spectral analysis of -vector-valued time series there is often a need for good sh…