Semi-Supervised Learning of Visual Features by Non-Parametrically Predicting View Assignments with Support Samples

This paper proposes a novel method of learning by predicting view assignments with support samples (PAWS). The method trains a model to minimize a consistency loss, which ensures that different views of the same unlabeled instance are assigned similar pseudo-labels. The pseudo-labels are generated non-parametrically, by comparing the representations of the image views to those of a set of randomly sampled labeled images. The distance between the view representations and labeled representations is used to provide a weighting over class labels, which we interpret as a soft pseudo-label. By non-parametrically incorporating labeled samples in this way, PAWS extends the distance-metric loss used in self-supervised methods such as BYOL and SwAV to the semi-supervised setting. Despite the simplicity of the approach, PAWS outperforms other semi-supervised methods across architectures, setting a new state-of-the-art for a ResNet-50 on ImageNet trained with either 10% or 1% of the labels, reaching 75.5% and 66.5% top-1 respectively. PAWS requires 4x to 12x less training than the previous best methods.

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Task Dataset Model Metric Name Metric Value Global Rank Result Benchmark
Semi-Supervised Image Classification CIFAR-10, 4000 Labels PAWS-NN (WRN-28-2) Percentage error 4.0 ± 0.25 # 4
Image Classification ImageNet PAWS (ResNet-50, 10% labels) Top 1 Accuracy 75.5% # 874
Image Classification ImageNet PAWS (ResNet-50, 1% labels) Top 1 Accuracy 66.5% # 966
Semi-Supervised Image Classification ImageNet - 10% labeled data PAWS (ResNet-50 2x) Top 1 Accuracy 77.8% # 12
Semi-Supervised Image Classification ImageNet - 10% labeled data PAWS (ResNet-50 4x) Top 1 Accuracy 79.0% # 9
Semi-Supervised Image Classification ImageNet - 10% labeled data PAWS (ResNet-50) Top 1 Accuracy 75.5% # 17
Semi-Supervised Image Classification ImageNet - 1% labeled data PAWS (ResNet-50) Top 1 Accuracy 66.5% # 22
Semi-Supervised Image Classification ImageNet - 1% labeled data PAWS (ResNet-50 2x) Top 1 Accuracy 69.6% # 15
Semi-Supervised Image Classification ImageNet - 1% labeled data PAWS (ResNet-50 4x) Top 1 Accuracy 69.9% # 14

Methods