Hyperspherical Classification with Dynamic Label-to-Prototype Assignment
<|reference_start|>Hyperspherical Classification with Dynamic Label-to-Prototype Assignment: Aiming to enhance the utilization of metric space by the parametric softmax classifier, recent studies suggest replacing it with a non-parametric alternative. Although a non-parametric classifier may provide better metric space utilization, it introduces the challenge of capturing inter-class relationships. A shared characteristic among prior non-parametric classifiers is the static assignment of labels to prototypes during the training, ie, each prototype consistently represents a class throughout the training course. Orthogonal to previous works, we present a simple yet effective method to optimize the category assigned to each prototype (label-to-prototype assignment) during the training. To this aim, we formalize the problem as a two-step optimization objective over network parameters and label-to-prototype assignment mapping. We solve this optimization using a sequential combination of gradient descent and Bipartide matching. We demonstrate the benefits of the proposed approach by conducting experiments on balanced and long-tail classification problems using different backbone network architectures. In particular, our method outperforms its competitors by 1.22\% accuracy on CIFAR-100, and 2.15\% on ImageNet-200 using a metric space dimension half of the size of its competitors. Code: https://github.com/msed-Ebrahimi/DL2PA_CVPR24<|reference_end|>
@article{saadabadi2024hyperspherical,
    title={Hyperspherical Classification with Dynamic Label-to-Prototype Assignment},
    author={Mohammad Saeed Ebrahimi Saadabadi, Ali Dabouei, Sahar Rahimi
  Malakshan, Nasser M. Nasrabad},
    journal={arXiv preprint arXiv:2403.16937},
    year={2024},
    archivePrefix={arXiv},
    eprint={2403.16937},
    primaryClass={cs.CV}
}