Why Approximate Matrix Square Root Outperforms Accurate SVD in Global Covariance Pooling?

@article{Song2021WhyAM,
  title={Why Approximate Matrix Square Root Outperforms Accurate SVD in Global Covariance Pooling?},
  author={Yue Song and N. Sebe and Wei Wang},
  journal={2021 IEEE/CVF International Conference on Computer Vision (ICCV)},
  year={2021},
  pages={1095-1103}
}
  • Yue SongN. SebeWei Wang
  • Published 6 May 2021
  • Computer Science
  • 2021 IEEE/CVF International Conference on Computer Vision (ICCV)
Global Covariance Pooling (GCP) aims at exploiting the second-order statistics of the convolutional feature. Its effectiveness has been demonstrated in boosting the classification performance of Convolutional Neural Networks (CNNs). Singular Value Decomposition (SVD) is used in GCP to compute the matrix square root. However, the approximate matrix square root calculated using Newton-Schulz iteration [14] outperforms the accurate one computed via SVD [15]. We empirically analyze the reason… 

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