SAX-Based GNN Embeddings for Time Series
2025 (English)In: 2025 25th International Conference on Digital Signal Processing, DSP 2025, Institute of Electrical and Electronics Engineers Inc. , 2025Conference paper, Published paper (Refereed)
Abstract [en]
Time series classification requires effective feature representations that capture temporal dependencies and structural patterns. Symbolic Aggregate approXimation (SAX) can reduce dimensionality while preserving essential time series patterns, but SAX-based approaches often lack contextual information beyond local symbol occurrences. Here, we introduce a novel method that combines SAX with Graph Neural Networks (GNNs), a robust deep learning framework that generates meaningful embeddings for time series classification. SAX words are extracted and structured as a directed graph, where consecutive words form weighted edges. GNN s are then applied to learn embeddings, which are classified using a Random Forest (RF) classifier. The method is evaluated on a diverse set of benchmark datasets from the UCR Time Series Archive, which provides insight into its performance across different types of time series data.
Place, publisher, year, edition, pages
Institute of Electrical and Electronics Engineers Inc. , 2025.
Series
International Conference on Digital Signal Processing (DSP), E-ISSN 2165-3577
Keywords [en]
SAX, BOP, graph, time series classification, GNNs
National Category
Computer Sciences
Research subject
Robotics and Artificial Intelligence
Identifiers
URN: urn:nbn:se:ltu:diva-114412DOI: 10.1109/DSP65409.2025.11075189ISI: 001556221900090Scopus ID: 2-s2.0-105012216461OAI: oai:DiVA.org:ltu-114412DiVA, id: diva2:1991676
Conference
2025 25th International Conference on Digital Signal Processing (DSP 2025), Costa Navarino, Greece, June 25-27, 2025
Projects
+NOMOS “Intelligent Legislation Management System using Machine Learning and Natural Language Processing Methods”
Note
Funder: Next Generation EU (ΥΠ3ΤΑ-0561468)
2025-08-252025-08-252026-04-07Bibliographically approved