Keywords: Partially-annotating, multi-label learning
Abstract: Precisely annotating instances with multiple labels is costly and has emerged as a significant bottleneck in the real-world multi-label learning tasks. To deal with this problem, the most straightforward strategy is partially-annotating, which aims to reduce the cost by annotating only a subset of labels. Existing works mainly includes label-level partially-annotating (LPA), where each instance is assigned a subset of positive labels, and instance-level partially-annotating (IPA), where all positive labels are assigned to an instance, but only a subset of instances are annotated. However, these methods tend to focus on improving model performance under each type of partial annotation, often neglecting a fundamental question: \textit{which method is the most cost-effective?} In this paper, we empirically evaluate which partially-annotating method achieves better model performance at the same annotation cost. To make a fair comparison, we manually annotated images in the MS-COCO dataset using two partially-annotating methods and recorded their averaging annotation time per image. This allows us to train models on two types of partial annotations with the same annotation cost and to compare their performance. Empirical results show that even when the number of examples annotated with IPA is only one-fifth that of LPA, models trained on IPA annotations significantly outperform those trained on LPA annotations, yielding that IPA is significantly more cost-effective than LPA. To explain the superiority of IPA, our causal reasoning framework shows that compared to LPA, IPA preserves complete co-occurrence relationships, enabling the model to capture correlative patterns, which is useful for improving model performance.
Primary Area: unsupervised, self-supervised, semi-supervised, and supervised representation learning
Code Of Ethics: I acknowledge that I and all co-authors of this work have read and commit to adhering to the ICLR Code of Ethics.
Submission Guidelines: I certify that this submission complies with the submission instructions as described on https://iclr.cc/Conferences/2025/AuthorGuide.
Reciprocal Reviewing: I understand the reciprocal reviewing requirement as described on https://iclr.cc/Conferences/2025/CallForPapers. If none of the authors are registered as a reviewer, it may result in a desk rejection at the discretion of the program chairs. To request an exception, please complete this form at https://forms.gle/Huojr6VjkFxiQsUp6.
Anonymous Url: I certify that there is no URL (e.g., github page) that could be used to find authors’ identity.
No Acknowledgement Section: I certify that there is no acknowledgement section in this submission for double blind review.
Submission Number: 13129
Loading