Instance Credibility Inference for Few-Shot Learning
Yikai Wang, Chengming Xu, Chen Liu, Li Zhang, Yanwei Fu
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ReproduceCode
- github.com/Yikai-Wang/ICI-FSLOfficialIn paperpytorch★ 85
Abstract
Few-shot learning (FSL) aims to recognize new objects with extremely limited training data for each category. Previous efforts are made by either leveraging meta-learning paradigm or novel principles in data augmentation to alleviate this extremely data-scarce problem. In contrast, this paper presents a simple statistical approach, dubbed Instance Credibility Inference (ICI) to exploit the distribution support of unlabeled instances for few-shot learning. Specifically, we first train a linear classifier with the labeled few-shot examples and use it to infer the pseudo-labels for the unlabeled data. To measure the credibility of each pseudo-labeled instance, we then propose to solve another linear regression hypothesis by increasing the sparsity of the incidental parameters and rank the pseudo-labeled instances with their sparsity degree. We select the most trustworthy pseudo-labeled instances alongside the labeled examples to re-train the linear classifier. This process is iterated until all the unlabeled samples are included in the expanded training set, i.e. the pseudo-label is converged for unlabeled data pool. Extensive experiments under two few-shot settings show that our simple approach can establish new state-of-the-arts on four widely used few-shot learning benchmark datasets including miniImageNet, tieredImageNet, CIFAR-FS, and CUB. Our code is available at: https://github.com/Yikai-Wang/ICI-FSL
Tasks
Benchmark Results
| Dataset | Model | Metric | Claimed | Verified | Status |
|---|---|---|---|---|---|
| CIFAR-FS 5-way (1-shot) | ICI | Accuracy | 76.51 | — | Unverified |
| CIFAR-FS 5-way (5-shot) | ICI | Accuracy | 84.32 | — | Unverified |
| CUB 200 5-way 1-shot | ICI | Accuracy | 89.58 | — | Unverified |
| CUB 200 5-way 5-shot | ICI | Accuracy | 92.48 | — | Unverified |
| Dirichlet Mini-Imagenet (5-way, 1-shot) | LR-ICI | 1:1 Accuracy | 58.7 | — | Unverified |
| Dirichlet Mini-Imagenet (5-way, 5-shot) | LR-ICI | 1:1 Accuracy | 73.5 | — | Unverified |
| Dirichlet Tiered-Imagenet (5-way, 1-shot) | LR+ICI | 1:1 Accuracy | 74.6 | — | Unverified |
| Dirichlet Tiered-Imagenet (5-way, 5-shot) | LR+ICI | 1:1 Accuracy | 85.1 | — | Unverified |
| Mini-Imagenet 5-way (1-shot) | ICI | Accuracy | 69.66 | — | Unverified |
| Mini-Imagenet 5-way (5-shot) | ICI | Accuracy | 80.11 | — | Unverified |
| Tiered ImageNet 5-way (1-shot) | ICI | Accuracy | 84.01 | — | Unverified |
| Tiered ImageNet 5-way (5-shot) | ICI | Accuracy | 89 | — | Unverified |