arXiv Machine Learning By Praditha Alwis, Soumyadeep Chandra, Deepak Ravikumar, Kaushik Roy

Loss Knows Best: Detecting Annotation Errors in Videos via Loss Trajectories

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The paper introduces Cumulative Sample Loss (CSL), a metric derived from checkpoint loss dynamics, to detect annotation errors in temporally labeled videos. CSL captures persistent disagreement between a frame’s annotation and the learned visual‑temporal structure, flagging high‑CSL frames as likely mislabeling or temporal disordering. Experiments on EgoPER and Cholec80 show CSL outperforming final‑checkpoint loss, achieving up to a 4.2‑point AUC improvement on EgoPER and 92.0/78.5 AUC on Cholec80.

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