CroSSL: Cross-modal Self-Supervised Learning for Time-series through Latent Masking

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Deldari, Shohreh, Spathis, Dimitris, Malekzadeh, Mohammad, Kawsar, Fahim, Salim, Flora, Mathur, Akhil
Format: Preprint
Published: 2023
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866911779198599168
author Deldari, Shohreh
Spathis, Dimitris
Malekzadeh, Mohammad
Kawsar, Fahim
Salim, Flora
Mathur, Akhil
author_facet Deldari, Shohreh
Spathis, Dimitris
Malekzadeh, Mohammad
Kawsar, Fahim
Salim, Flora
Mathur, Akhil
contents Limited availability of labeled data for machine learning on multimodal time-series extensively hampers progress in the field. Self-supervised learning (SSL) is a promising approach to learning data representations without relying on labels. However, existing SSL methods require expensive computations of negative pairs and are typically designed for single modalities, which limits their versatility. We introduce CroSSL (Cross-modal SSL), which puts forward two novel concepts: masking intermediate embeddings produced by modality-specific encoders, and their aggregation into a global embedding through a cross-modal aggregator that can be fed to down-stream classifiers. CroSSL allows for handling missing modalities and end-to-end cross-modal learning without requiring prior data preprocessing for handling missing inputs or negative-pair sampling for contrastive learning. We evaluate our method on a wide range of data, including motion sensors such as accelerometers or gyroscopes and biosignals (heart rate, electroencephalograms, electromyograms, electrooculograms, and electrodermal) to investigate the impact of masking ratios and masking strategies for various data types and the robustness of the learned representations to missing data. Overall, CroSSL outperforms previous SSL and supervised benchmarks using minimal labeled data, and also sheds light on how latent masking can improve cross-modal learning. Our code is open-sourced at https://github.com/dr-bell/CroSSL.
format Preprint
id arxiv_https___arxiv_org_abs_2307_16847
institution arXiv
publishDate 2023
record_format arxiv
spellingShingle CroSSL: Cross-modal Self-Supervised Learning for Time-series through Latent Masking
Deldari, Shohreh
Spathis, Dimitris
Malekzadeh, Mohammad
Kawsar, Fahim
Salim, Flora
Mathur, Akhil
Machine Learning
Limited availability of labeled data for machine learning on multimodal time-series extensively hampers progress in the field. Self-supervised learning (SSL) is a promising approach to learning data representations without relying on labels. However, existing SSL methods require expensive computations of negative pairs and are typically designed for single modalities, which limits their versatility. We introduce CroSSL (Cross-modal SSL), which puts forward two novel concepts: masking intermediate embeddings produced by modality-specific encoders, and their aggregation into a global embedding through a cross-modal aggregator that can be fed to down-stream classifiers. CroSSL allows for handling missing modalities and end-to-end cross-modal learning without requiring prior data preprocessing for handling missing inputs or negative-pair sampling for contrastive learning. We evaluate our method on a wide range of data, including motion sensors such as accelerometers or gyroscopes and biosignals (heart rate, electroencephalograms, electromyograms, electrooculograms, and electrodermal) to investigate the impact of masking ratios and masking strategies for various data types and the robustness of the learned representations to missing data. Overall, CroSSL outperforms previous SSL and supervised benchmarks using minimal labeled data, and also sheds light on how latent masking can improve cross-modal learning. Our code is open-sourced at https://github.com/dr-bell/CroSSL.
title CroSSL: Cross-modal Self-Supervised Learning for Time-series through Latent Masking
topic Machine Learning
url https://arxiv.org/abs/2307.16847