Deep neural networks may perform poorly when training datasets are heavily class-imbalanced. Recently, two-stage methods decouple representation learning and classifier learning to improve performance. But there is still the vital issue of miscalibration. To address it, we design two methods to improve calibration and performance in such scenarios. Motivated by the fact that predicted probability distributions of classes are highly related to the numbers of class instances, we propose label-aware smoothing to deal with different degrees of over-confidence for classes and improve classifier learning. For dataset bias between these two stages due to different samplers, we further propose shifted batch normalization in the decoupling framework. Our proposed methods set new records on multiple popular long-tailed recognition benchmark datasets, including CIFAR-10-LT, CIFAR-100-LT, ImageNet-LT, Places-LT, and iNaturalist 2018. Code will be available at https://github.com/Jia-Research-Lab/MiSLAS.
翻译:当培训数据集高度分类平衡时,深神经网络可能表现不佳。 最近,两阶段方法将代表制学习和分类者学习结合起来,以提高绩效。 但是,仍然存在着重要的校正错误问题。为了解决这个问题,我们设计了两种方法来改进这类情景的校准和性能。由于预计的班级概率分布与班级案例数量高度相关,我们提议在标签上保持平稳,以应对班级过度信任的不同程度,并改善叙级学习。对于由于不同采样者而导致的这两个阶段之间的数据集偏差,我们进一步提议在脱钩框架中改变批次正常化。我们提议的方法在多个受欢迎的长期确认基准数据集上设置了新的记录,包括CIFAR-10-LT、CIFAR-100-LT、图像网-LT、Plocks-LT和iNatallist 2018。代码将在https://github.com/Jia-Research-Lab/MISLAS上公布。