Academic Journal

Quick Adaptive Ternary Segmentation: An Efficient Decoding Procedure For Hidden Markov Models.

Λεπτομέρειες βιβλιογραφικής εγγραφής
Τίτλος: Quick Adaptive Ternary Segmentation: An Efficient Decoding Procedure For Hidden Markov Models.
Συγγραφείς: Mösching, Alexandre1 (AUTHOR), Li, Housen2 (AUTHOR) housen.li@mathematik.uni-goettingen.de, Munk, Axel2 (AUTHOR)
Πηγή: Journal of Computational & Graphical Statistics. Apr-Jun2026, Vol. 35 Issue 2, p865-879. 15p.
Θεματικοί όροι: *Algorithms, Hidden Markov models, Decoding algorithms, Computational complexity, Maximum likelihood statistics, Viterbi decoding, Storage
Περίληψη: Hidden Markov models (HMMs) are characterized by an unobservable Markov chain and an observable process—a noisy version of the hidden chain. Decoding the original signal from the noisy observations is one of the main goals in nearly all HMM based data analyses. Existing decoding algorithms such as Viterbi and the pointwise maximum a posteriori (PMAP) algorithm have computational complexity at best linear in the length of the observed sequence, and sub-quadratic in the size of the state space of the hidden chain. We present Quick Adaptive Ternary Segmentation (QATS), a divide-and-conquer procedure with computational complexity polylogarithmic in the length of the sequence, and cubic in the size of the state space, hence, particularly suited for large scale HMMs with relatively few states. It also suggests an effective way of data storage as specific cumulative sums. In essence, the estimated sequence of states sequentially maximizes local likelihood scores among all local paths with at most three segments, and is meanwhile admissible. The maximization is performed only approximately using an adaptive search procedure. Our simulations demonstrate the speedups offered by QATS in comparison to Viterbi and PMAP, along with a precision analysis. An implementation of QATS is in the R-package QATS on GitHub. Supplementary materials for this article are available online. [ABSTRACT FROM AUTHOR]
Copyright of Journal of Computational & Graphical Statistics is the property of Taylor & Francis Ltd and its content may not be copied or emailed to multiple sites without the copyright holder's express written permission. Additionally, content may not be used with any artificial intelligence tools or machine learning technologies. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
Βάση Δεδομένων: Business Source Index