Skip to main content Accessibility help
×
Hostname: page-component-848d4c4894-wzw2p Total loading time: 0 Render date: 2024-06-02T02:27:28.994Z Has data issue: false hasContentIssue false

3 - A note on a complex Hilbert metric with application to domain of analyticity for entropy rate of hidden Markov processes

Published online by Cambridge University Press:  05 June 2011

Guangyue Han
Affiliation:
University of Hong Kong
Brian Marcus
Affiliation:
University of British Columbia
Yuval Peres
Affiliation:
University of California at Berkeley
Brian Marcus
Affiliation:
University of British Columbia, Vancouver
Karl Petersen
Affiliation:
University of North Carolina, Chapel Hill
Tsachy Weissman
Affiliation:
Stanford University, California
Get access

Summary

Abstract. In this article, we show that small complex perturbations of positive matrices are contractions, with respect to a complex version of the Hilbert metric, on a neighborhood of the interior of the real simplex within the complex simplex. We show that this metric can be used to obtain estimates of the domain of analyticity of the entropy rate for a hidden Markov process when the underlying Markov chain has strictly positive transition probabilities.

Introduction

The purpose of this article is twofold. First, in Section 2, we introduce a new complex version of the Hilbert metric on the standard real simplex. This metric is defined on a complex neighborhood of the interior of the standard real simplex, within the standard complex simplex. We show that if the neighborhood is sufficiently small, then any sufficiently small complex perturbation of a strictly positive square matrix acts as a contraction, with respect to this metric. While this article was nearing completion, we were informed of a different complex Hilbert metric, which was recently introduced. We briefly discuss the relation between this metric [3] and our metric in Remark 2.7.

Secondly, we show how one can use a complex Hilbert metric to obtain lower estimates of the domain of analyticity of the entropy rate for a hidden Markov process when the underlying Markov chain has strictly positive transition probabilities.

Type
Chapter
Information
Entropy of Hidden Markov Processes and Connections to Dynamical Systems
Papers from the Banff International Research Station Workshop
, pp. 98 - 116
Publisher: Cambridge University Press
Print publication year: 2011

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

Save book to Kindle

To save this book to your Kindle, first ensure coreplatform@cambridge.org is added to your Approved Personal Document E-mail List under your Personal Document Settings on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part of your Kindle email address below. Find out more about saving to your Kindle.

Note you can select to save to either the @free.kindle.com or @kindle.com variations. ‘@free.kindle.com’ emails are free but can only be saved to your device when it is connected to wi-fi. ‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.

Find out more about the Kindle Personal Document Service.

Available formats
×

Save book to Dropbox

To save content items to your account, please confirm that you agree to abide by our usage policies. If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account. Find out more about saving content to Dropbox.

Available formats
×

Save book to Google Drive

To save content items to your account, please confirm that you agree to abide by our usage policies. If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account. Find out more about saving content to Google Drive.

Available formats
×