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Title: Open Anomalous Trajectory Recognition via Probabilistic Metric Learning
Typically, trajectories considered anomalous are the ones deviating from usual (e.g., traffic-dictated) driving patterns. However, this closed-set context fails to recognize the unknown anomalous trajectories, resulting in an insufficient self-motivated learning paradigm. In this study, we investigate the novel Anomalous Trajectory Recognition problem in an Open-world scenario (ATRO) and introduce a novel probabilistic Metric learning model, namely ATROM, to address it. Specifically, ATROM can detect the presence of unknown anomalous behavior in addition to identifying known behavior. It has a Mutual Interaction Distillation that uses contrastive metric learning to explore the interactive semantics regarding the diverse behavioral intents and a Probabilistic Trajectory Embedding that forces the trajectories with distinct behaviors to follow different Gaussian priors. More importantly, ATROM offers a probabilistic metric rule to discriminate between known and unknown behavioral patterns by taking advantage of the approximation of multiple priors. Experimental results on two large-scale trajectory datasets demonstrate the superiority of ATROM in addressing both known and unknown anomalous patterns.  more » « less
Award ID(s):
2030249
PAR ID:
10488101
Author(s) / Creator(s):
; ; ; ; ;
Publisher / Repository:
International Joint Conferences on Artificial Intelligence Organization
Date Published:
Journal Name:
IJCAI
ISSN:
1045-0823
ISBN:
978-1-956792-03-4
Page Range / eLocation ID:
2095 to 2103
Format(s):
Medium: X
Location:
Macau, SAR China
Sponsoring Org:
National Science Foundation
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