Towards Debiasing Frame Length Bias in Text-Video Retrieval via Causal Intervention

Published in BMVC 2023, 2023

Burak Satar1,2, Hongyuan Zhu1, Hanwang Zhang2, Joo-Hwee Lim1,2

1Institute for Infocomm Research (I2R), A*STAR  ·  2College of Computing and Data Science (formerly SCSE), Nanyang Technological University

Shows that text-video retrieval models exploit clip length as a shortcut, and mitigates the bias with causal intervention.

Structural causal model showing how clip length confounds the match between a text query and a video.

Abstract

Many studies focus on improving pretraining or developing new backbones in text-video retrieval. However, existing methods may suffer from the learning and inference bias issue, as recent research suggests in other text-video-related tasks. For instance, spatial appearance features on action recognition or temporal object co-occurrences on video scene graph generation could induce spurious correlations. In this work, we present a unique and systematic study of a temporal bias due to frame length discrepancy between training and test sets of trimmed video clips, which is the first such attempt for a text-video retrieval task, to the best of our knowledge. We first hypothesise and verify the bias on how it would affect the model illustrated with a baseline study. Then, we propose a causal debiasing approach and perform extensive experiments and ablation studies on the Epic-Kitchens-100, YouCook2, and MSR-VTT datasets. Our model overpasses the baseline and SOTA on nDCG, a semantic-relevancy-focused evaluation metric which proves the bias is mitigated, as well as on the other conventional metrics.

Video

Acknowledgements

This research is supported by the Agency for Science, Technology and Research (A*STAR) under its AME Programmatic Funding Scheme (Project A18A2b0046).

BibTeX
@inproceedings{satar-etal-2023-frame-length,
  author       = {Burak Satar and
                  Hongyuan Zhu and
                  Hanwang Zhang and
                  Joo{-}Hwee Lim},
  title        = {Towards Debiasing Frame Length Bias in Text-Video Retrieval via Causal
                  Intervention},
  booktitle    = {34th British Machine Vision Conference 2023, {BMVC} 2023, Aberdeen,
                  UK, November 20-24, 2023},
  pages        = {650--658},
  publisher    = {{BMVA} Press},
  year         = {2023},
  url          = {https://papers.bmvc2023.org/0650.pdf},
  biburl       = {https://dblp.org/rec/conf/bmvc/SatarZZL23.bib},
  bibsource    = {dblp computer science bibliography, https://dblp.org}
}