Semi-supervised learning (SSL) provides a powerful framework for leveraging unlabeled data when labels are limited or expensive to obtain. SSL algorithms based on deep neural networks have recently proven successful on standard benchmark tasks. However, we argue that these benchmarks fail to address many issues that these algorithms would face in real-world applications. After creating a unified reimplementation of various widely-used SSL techniques, we test them in a suite of experiments designed to address these issues. We find that the performance of simple baselines which do not use unlabeled data is often underreported, that SSL methods differ in sensitivity to the amount of labeled and unlabeled data, and that performance can degrade substantially when the unlabeled dataset contains out-of-class examples. To help guide SSL research towards real-world applicability, we make our unified reimplemention and evaluation platform publicly available.

通过实现多种常用的 SSL 技术并在一系列实验中进行测试，研究发现简单基线方法的表现通常被低估，而 SSL 方法对标记和未标记数据的敏感性不同，当未标记数据集包含类外示例时性能可能会显著下降，因此我们提供了一个公共代码重现平台以帮助实现 SSL 技术在实际应用中的可行性。

深度半监督学习算法的实际评估