On computing the total variation distance of hidden Markov models

We prove results on the decidability and complexity of computing the total variation distance (equivalently, the L1-distance) of hidden Markov models (equivalently, labelled Markov chains). This distance measures the difference between the distributions on words that two hidden Markov models induce....

Full description

Bibliographic Details
Main Author: Kiefer, S
Format: Conference item
Published: Schloss Dagstuhl 2018
Description
Summary:We prove results on the decidability and complexity of computing the total variation distance (equivalently, the L1-distance) of hidden Markov models (equivalently, labelled Markov chains). This distance measures the difference between the distributions on words that two hidden Markov models induce. The main results are: (1) it is undecidable whether the distance is greater than a given threshold; (2) approximation is #P-hard and in PSPACE.