Do We Really Need a Learnable Classifier at the End of Deep Neural Network?

  title={Do We Really Need a Learnable Classifier at the End of Deep Neural Network?},
  author={Yibo Yang and Liangru Xie and Shixiang Chen and Xiangtai Li and Zhouchen Lin and Dacheng Tao},
Modern deep neural networks for classification usually jointly learn a backbone for representation and a linear classifier to output the logit of each class. A recent study has shown a phenomenon called neural collapse that the within-class means of features and the classifier vectors converge to the vertices of a simplex equiangular tight frame (ETF) at the terminal phase of training on a balanced dataset. Since the ETF geometric structure maximally separates the pair-wise angles of all classes… 

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