<p>Long-tailed
data is still a big challenge for deep neural networks, even though they have
achieved great success on balanced data. We observe that vanilla training on
long-tailed data with cross-entropy loss makes the instance-rich head classes
severely squeeze the spatial distribution of the tail classes, which leads to
difficulty in classifying tail class samples. Furthermore, the original
cross-entropy loss can only propagate gradient short-lively because the
gradient in softmax form rapidly approaches zero as the logit difference
increases. This phenomenon is called softmax saturation. It is unfavorable for
training on balanced data, but can be utilized to adjust the validity of the
samples in long-tailed data, thereby solving the distorted embedding space of
long-tailed problems. To this end, this paper therefore proposes the Gaussian
clouded logit adjustment by Gaussian perturbing different class logits with
varied amplitude. We define the amplitude of perturbation as cloud size and set
relatively large cloud sizes to tail classes. The large cloud size can reduce
the softmax saturation and thereby making tail class samples more active as
well as enlarging the embedding space. To alleviate the bias in the classifier,
we accordingly propose the class-based effective number sampling strategy with
classifier re-training. Extensive experiments on benchmark datasets validate
the superior performance of the proposed method.</p><br>