Papers › HYperbolic Self-Paced Learning for Self-Supervised Skeleton-based Action Representations

HYperbolic Self-Paced Learning for Self-Supervised Skeleton-based Action Representations

10 Mar 2023arXiv:2303.06242archive 2025-07-28

Luca Franco, Paolo Mandica, Bharti Munjal, Fabio Galasso

Self-paced learning has been beneficial for tasks where some initial knowledge is available, such as weakly supervised learning and domain adaptation, to select and order the training sample sequence, from easy to complex. However its applicability remains unexplored in unsupervised learning, whereby the knowledge of the task matures during training. We propose a novel HYperbolic Self-Paced model (HYSP) for learning skeleton-based action representations. HYSP adopts self-supervision: it uses data augmentations to generate two views of the same sample, and it learns by matching one (named online) to the other (the target). We propose to use hyperbolic uncertainty to determine the algorithmic learning pace, under the assumption that less uncertain samples should be more strongly driving the training, with a larger weight and pace. Hyperbolic uncertainty is a by-product of the adopted hyperbolic neural networks, it matures during training and it comes with no extra cost, compared to the established Euclidean SSL framework counterparts. When tested on three established skeleton-based action recognition datasets, HYSP outperforms the state-of-the-art on PKU-MMD I, as well as on 2 out of 3 downstream tasks on NTU-60 and NTU-120. Additionally, HYSP only uses positive pairs and bypasses therefore the complex and computationally-demanding mining procedures required for the negatives in contrastive techniques. Code is available at https://github.com/paolomandica/HYSP.

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EMA paolomandica/hysp/src/net/hysp.py official repository ran · metamorphic tier: deterministic MIT (permissive) · 8ba7eaf2c8a7739a · report
Simam_Drop paolomandica/hysp/src/net/hysp.py official repository ran · metamorphic tier: invariant fingerprinted MIT (permissive) · dd034bb1c67ea073 · report
DropBlockT_1d paolomandica/hysp/src/net/hysp.py official repository unverified MIT (permissive) · 180f114b9cbc15ea · report
DropBlock_Ske paolomandica/hysp/src/net/hysp.py official repository unverified MIT (permissive) · bc2bd6c395543b89 · report
Graph paolomandica/hysp/src/net/hysp.py official repository unverified MIT (permissive) · 2bbb5e685ad2f3b3 · report
HYSP paolomandica/hysp/src/net/hysp.py official repository unverified MIT (permissive) · 90735a76fd308958 · report
HyperMapper paolomandica/hysp/src/net/hysp.py official repository unverified MIT (permissive) · 80f6560d69b89e68 · report
MLP paolomandica/hysp/src/net/hysp.py official repository unverified MIT (permissive) · 3a7a63e8f839cd58 · report
MobiusLinear paolomandica/hysp/src/net/hysp.py official repository unverified MIT (permissive) · 3b892a99281475cb · report
PositiveOnlyLoss paolomandica/hysp/src/net/hysp.py official repository unverified MIT (permissive) · 45cf805fdfb46a6c · report
_mobius_matvec paolomandica/hysp/src/net/hysp.py official repository unverified MIT (permissive) · bc7290a25a803047 · report
mobius_linear paolomandica/hysp/src/net/hysp.py official repository unverified MIT (permissive) · 59823bc0371d269d · report
mobius_matvec paolomandica/hysp/src/net/hysp.py official repository unverified MIT (permissive) · 46dd9b384ab6543c · report

Tasks

Action RecognitionDomain AdaptationSkeleton Based Action RecognitionUnsupervised Skeleton Based Action RecognitionWeakly-supervised Learning

Results from the paper archive 2025-07-28

TaskDatasetModelMetricValueRank at snapshotLeaderboardReport
Skeleton Based Action Recognition NTU RGB+D 3s-HYSP Accuracy (CS) 89.1 #65 of 135 Archive leaderboard report
Skeleton Based Action Recognition NTU RGB+D 3s-HYSP Accuracy (CV) 95.2 #65 of 135 Archive leaderboard report
Skeleton Based Action Recognition NTU RGB+D HYSP Accuracy (CS) 86.5 #83 of 135 Archive leaderboard report
Skeleton Based Action Recognition NTU RGB+D HYSP Accuracy (CV) 93.5 #83 of 135 Archive leaderboard report
Skeleton Based Action Recognition NTU RGB+D 120 3s-HYSP Accuracy (Cross-Setup) 86.3 #49 of 83 Archive leaderboard report
Skeleton Based Action Recognition NTU RGB+D 120 3s-HYSP Accuracy (Cross-Subject) 84.5 #49 of 83 Archive leaderboard report
Skeleton Based Action Recognition NTU RGB+D 120 HYSP Accuracy (Cross-Setup) 82 #54 of 83 Archive leaderboard report
Skeleton Based Action Recognition NTU RGB+D 120 HYSP Accuracy (Cross-Subject) 81.4 #54 of 83 Archive leaderboard report
Skeleton Based Action Recognition PKU-MMD 3s-HYSP Accuracy (Cross-Subject) 96.2 #4 of 4 Archive leaderboard report

Ranks are positions in the archive's leaderboards as they stood at the 2025-07-28 snapshot. Results published since then are not among these rows, so a rank here is not a current standing.

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