论文标题
迅速驱动的有效开放设定半监督学习
Prompt-driven efficient Open-set Semi-supervised Learning
论文作者
论文摘要
开放设定的半监督学习（OSSL）引起了人们日益增长的兴趣，该学习调查了一个更实用的情况，在该场景中，无标记的数据中仅包含过分分布（OOD）样本。现有的OSSL方法（例如OpenMatch）学习一个OOD检测器以识别离群值，该检测器通常会更新所有模态参数（即完整的微调），以从标记的数据传播类信息到未标记的数据。当前，已经开发了及时的学习来弥合预训练和微调之间的差距，这在几个下游任务中显示出较高的计算效率。在本文中，我们提出了一个迅速驱动的有效OSSL框架，称为OpenPrompt，该框架可以将类别的类信息传播到标记到未标记数据的类信息，只有少数可训练的参数。我们提出了一种迅速驱动的关节空间学习机制来检测OOD数据，通过在未标记的数据中最大化ID和OOD样本之间的分布差距，从而使我们的方法可以以新的方式检测到异常值。三个公共数据集的实验结果表明，OpenPrompt优于不到1％可训练参数的最先进方法。更重要的是，OpenPrompt在CIFAR10上完全有监督的模型上的AUROC检测方面取得了4％的改善。
Open-set semi-supervised learning (OSSL) has attracted growing interest, which investigates a more practical scenario where out-of-distribution (OOD) samples are only contained in unlabeled data. Existing OSSL methods like OpenMatch learn an OOD detector to identify outliers, which often update all modal parameters (i.e., full fine-tuning) to propagate class information from labeled data to unlabeled ones. Currently, prompt learning has been developed to bridge gaps between pre-training and fine-tuning, which shows higher computational efficiency in several downstream tasks. In this paper, we propose a prompt-driven efficient OSSL framework, called OpenPrompt, which can propagate class information from labeled to unlabeled data with only a small number of trainable parameters. We propose a prompt-driven joint space learning mechanism to detect OOD data by maximizing the distribution gap between ID and OOD samples in unlabeled data, thereby our method enables the outliers to be detected in a new way. The experimental results on three public datasets show that OpenPrompt outperforms state-of-the-art methods with less than 1% of trainable parameters. More importantly, OpenPrompt achieves a 4% improvement in terms of AUROC on outlier detection over a fully supervised model on CIFAR10.
