由于错误的自动和人类注释程序,NLP中的大型数据集遭受嘈杂的标签。我们研究了标签噪声的文本分类问题,并旨在通过分类器上通过辅助噪声模型捕获这种噪声。我们首先将概率得分分配给每个训练样本,通过训练早期纪要的损失的β混合模型来分配嘈杂的标签。然后,我们使用这个分数来选择性地引导噪声模型和分类器的学习。我们对两种文本分类任务的实证评估表明,我们的方法可以改善基线精度,并防止对噪声过度接近。
translated by 谷歌翻译
Despite being robust to small amounts of label noise, convolutional neural networks trained with stochastic gradient methods have been shown to easily fit random labels. When there are a mixture of correct and mislabelled targets, networks tend to fit the former before the latter. This suggests using a suitable two-component mixture model as an unsupervised generative model of sample loss values during training to allow online estimation of the probability that a sample is mislabelled. Specifically, we propose a beta mixture to estimate this probability and correct the loss by relying on the network prediction (the so-called bootstrapping loss). We further adapt mixup augmentation to drive our approach a step further. Experiments on CIFAR-10/100 and TinyImageNet demonstrate a robustness to label noise that substantially outperforms recent state-of-the-art. Source code is available at https://git.io/fjsvE.
translated by 谷歌翻译
大型电子商务产品数据中的嘈杂标签(即,将产品项放入错误类别)是产品分类任务的关键问题,因为它们是不可避免的,不足以显着删除和降低预测性能。培训数据中对数据中嘈杂标签的产品标题分类模型对于使产品分类应用程序更加实用非常重要。在本文中,我们通过比较我们的数据降低算法和不同的噪声抗压训练算法来研究实例依赖性噪声对产品标题分类的性能的影响,这些算法旨在防止分类器模型过度拟合到噪声。我们开发了一个简单而有效的深度神经网络,用于将产品标题分类用作基本分类器。除了刺激实例依赖性噪声的最新方法外,我们还提出了一种基于产品标题相似性的新型噪声刺激算法。我们的实验涵盖了多个数据集,各种噪声方法和不同的训练解决方案。当噪声速率不容易忽略时,结果揭示了分类任务的限制,并且数据分布高度偏斜。
translated by 谷歌翻译
Deep neural networks are known to be annotation-hungry. Numerous efforts have been devoted to reducing the annotation cost when learning with deep networks. Two prominent directions include learning with noisy labels and semi-supervised learning by exploiting unlabeled data. In this work, we propose DivideMix, a novel framework for learning with noisy labels by leveraging semi-supervised learning techniques. In particular, DivideMix models the per-sample loss distribution with a mixture model to dynamically divide the training data into a labeled set with clean samples and an unlabeled set with noisy samples, and trains the model on both the labeled and unlabeled data in a semi-supervised manner. To avoid confirmation bias, we simultaneously train two diverged networks where each network uses the dataset division from the other network. During the semi-supervised training phase, we improve the MixMatch strategy by performing label co-refinement and label co-guessing on labeled and unlabeled samples, respectively. Experiments on multiple benchmark datasets demonstrate substantial improvements over state-of-the-art methods. Code is available at https://github.com/LiJunnan1992/DivideMix.
translated by 谷歌翻译
Convolutional Neural Networks (CNNs) have demonstrated superiority in learning patterns, but are sensitive to label noises and may overfit noisy labels during training. The early stopping strategy averts updating CNNs during the early training phase and is widely employed in the presence of noisy labels. Motivated by biological findings that the amplitude spectrum (AS) and phase spectrum (PS) in the frequency domain play different roles in the animal's vision system, we observe that PS, which captures more semantic information, can increase the robustness of DNNs to label noise, more so than AS can. We thus propose early stops at different times for AS and PS by disentangling the features of some layer(s) into AS and PS using Discrete Fourier Transform (DFT) during training. Our proposed Phase-AmplituDe DisentangLed Early Stopping (PADDLES) method is shown to be effective on both synthetic and real-world label-noise datasets. PADDLES outperforms other early stopping methods and obtains state-of-the-art performance.
translated by 谷歌翻译
Large-scale supervised datasets are crucial to train convolutional neural networks (CNNs) for various computer vision problems. However, obtaining a massive amount of well-labeled data is usually very expensive and time consuming. In this paper, we introduce a general framework to train CNNs with only a limited number of clean labels and millions of easily obtained noisy labels. We model the relationships between images, class labels and label noises with a probabilistic graphical model and further integrate it into an end-to-end deep learning system. To demonstrate the effectiveness of our approach, we collect a large-scale real-world clothing classification dataset with both noisy and clean labels. Experiments on this dataset indicate that our approach can better correct the noisy labels and improves the performance of trained CNNs.
translated by 谷歌翻译
在监督的机器学习中,使用正确的标签对于确保高精度非常重要。不幸的是,大多数数据集都包含损坏的标签。在此类数据集上训练的机器学习模型不能很好地概括。因此,检测其标签错误可以显着提高其功效。我们提出了一个名为CTRL的新型框架(标签错误检测的聚类训练损失),以检测多级数据集中的标签错误。它基于模型以不同方式学习干净和嘈杂的标签的观察结果,以两个步骤检测标签错误。首先,我们使用嘈杂的训练数据集训练神经网络,并为每个样本获得损失曲线。然后,我们将聚类算法应用于训练损失,将样本分为两类:已标记和噪声标记。标签误差检测后,我们删除带有嘈杂标签的样品并重新训练该模型。我们的实验结果表明,在模拟噪声下,图像(CIFAR-10和CIFAR-100和CIFAR-100)和表格数据集上的最新误差检测准确性。我们还使用理论分析来提供有关CTRL表现如此出色的见解。
translated by 谷歌翻译
Deep neural networks may easily memorize noisy labels present in real-world data, which degrades their ability to generalize. It is therefore important to track and evaluate the robustness of models against noisy label memorization. We propose a metric, called susceptibility, to gauge such memorization for neural networks. Susceptibility is simple and easy to compute during training. Moreover, it does not require access to ground-truth labels and it only uses unlabeled data. We empirically show the effectiveness of our metric in tracking memorization on various architectures and datasets and provide theoretical insights into the design of the susceptibility metric. Finally, we show through extensive experiments on datasets with synthetic and real-world label noise that one can utilize susceptibility and the overall training accuracy to distinguish models that maintain a low memorization on the training set and generalize well to unseen clean data.
translated by 谷歌翻译
Training accurate deep neural networks (DNNs) in the presence of noisy labels is an important and challenging task. Though a number of approaches have been proposed for learning with noisy labels, many open issues remain. In this paper, we show that DNN learning with Cross Entropy (CE) exhibits overfitting to noisy labels on some classes ("easy" classes), but more surprisingly, it also suffers from significant under learning on some other classes ("hard" classes). Intuitively, CE requires an extra term to facilitate learning of hard classes, and more importantly, this term should be noise tolerant, so as to avoid overfitting to noisy labels. Inspired by the symmetric KL-divergence, we propose the approach of Symmetric cross entropy Learning (SL), boosting CE symmetrically with a noise robust counterpart Reverse Cross Entropy (RCE). Our proposed SL approach simultaneously addresses both the under learning and overfitting problem of CE in the presence of noisy labels. We provide a theoretical analysis of SL and also empirically show, on a range of benchmark and real-world datasets, that SL outperforms state-of-the-art methods. We also show that SL can be easily incorporated into existing methods in order to further enhance their performance.
translated by 谷歌翻译
对标签噪声的学习是一个至关重要的话题,可以保证深度神经网络的可靠表现。最近的研究通常是指具有模型输出概率和损失值的动态噪声建模,然后分离清洁和嘈杂的样本。这些方法取得了显着的成功。但是,与樱桃挑选的数据不同,现有方法在面对不平衡数据集时通常无法表现良好,这是现实世界中常见的情况。我们彻底研究了这一现象,并指出了两个主要问题,这些问题阻碍了性能,即\ emph {类间损耗分布差异}和\ emph {由于不确定性而引起的误导性预测}。第一个问题是现有方法通常执行类不足的噪声建模。然而,损失分布显示在类失衡下的类别之间存在显着差异,并且类不足的噪声建模很容易与少数族裔类别中的嘈杂样本和样本混淆。第二个问题是指该模型可能会因认知不确定性和不确定性而导致的误导性预测,因此仅依靠输出概率的现有方法可能无法区分自信的样本。受我们的观察启发,我们提出了一个不确定性的标签校正框架〜(ULC)来处理不平衡数据集上的标签噪声。首先,我们执行认识不确定性的班级特异性噪声建模,以识别可信赖的干净样本并精炼/丢弃高度自信的真实/损坏的标签。然后,我们在随后的学习过程中介绍了不确定性,以防止标签噪声建模过程中的噪声积累。我们对几个合成和现实世界数据集进行实验。结果证明了提出的方法的有效性,尤其是在数据集中。
translated by 谷歌翻译
深神经网络(DNN)的记忆效果在许多最先进的标签噪声学习方法中起着枢轴作用。为了利用这一财产,通常采用早期停止训练早期优化的伎俩。目前的方法通常通过考虑整个DNN来决定早期停止点。然而,DNN可以被认为是一系列层的组成,并且发现DNN中的后一个层对标签噪声更敏感,而其前同行是非常稳健的。因此,选择整个网络的停止点可以使不同的DNN层对抗彼此影响,从而降低最终性能。在本文中,我们建议将DNN分离为不同的部位,逐步培训它们以解决这个问题。而不是早期停止,它一次列举一个整体DNN,我们最初通过用相对大量的时期优化DNN来训练前DNN层。在培训期间,我们通过使用较少数量的时期使用较少的地层来逐步培训后者DNN层,以抵消嘈杂标签的影响。我们将所提出的方法术语作为渐进式早期停止(PES)。尽管其简单性,与早期停止相比,PES可以帮助获得更有前景和稳定的结果。此外,通过将PE与现有的嘈杂标签培训相结合,我们在图像分类基准上实现了最先进的性能。
translated by 谷歌翻译
Semi-supervised learning based methods are current SOTA solutions to the noisy-label learning problem, which rely on learning an unsupervised label cleaner first to divide the training samples into a labeled set for clean data and an unlabeled set for noise data. Typically, the cleaner is obtained via fitting a mixture model to the distribution of per-sample training losses. However, the modeling procedure is \emph{class agnostic} and assumes the loss distributions of clean and noise samples are the same across different classes. Unfortunately, in practice, such an assumption does not always hold due to the varying learning difficulty of different classes, thus leading to sub-optimal label noise partition criteria. In this work, we reveal this long-ignored problem and propose a simple yet effective solution, named \textbf{C}lass \textbf{P}rototype-based label noise \textbf{C}leaner (\textbf{CPC}). Unlike previous works treating all the classes equally, CPC fully considers loss distribution heterogeneity and applies class-aware modulation to partition the clean and noise data. CPC takes advantage of loss distribution modeling and intra-class consistency regularization in feature space simultaneously and thus can better distinguish clean and noise labels. We theoretically justify the effectiveness of our method by explaining it from the Expectation-Maximization (EM) framework. Extensive experiments are conducted on the noisy-label benchmarks CIFAR-10, CIFAR-100, Clothing1M and WebVision. The results show that CPC consistently brings about performance improvement across all benchmarks. Codes and pre-trained models will be released at \url{https://github.com/hjjpku/CPC.git}.
translated by 谷歌翻译
深度学习的最新进展依赖于大型标签的数据集来培训大容量模型。但是,以时间和成本效益的方式收集大型数据集通常会导致标签噪声。我们提出了一种从嘈杂的标签中学习的方法,该方法利用特征空间中的训练示例之间的相似性,鼓励每个示例的预测与其最近的邻居相似。与使用多个模型或不同阶段的训练算法相比,我们的方法采用了简单,附加的正规化项的形式。它可以被解释为经典的,偏置标签传播算法的归纳版本。我们在数据集上彻底评估我们的方法评估合成(CIFAR-10,CIFAR-100)和现实(迷你网络,网络vision,Clotsing1m,Mini-Imagenet-Red)噪声,并实现竞争性或最先进的精度,在所有人之间。
translated by 谷歌翻译
深度神经网络模型对有限的标签噪声非常强大,但是它们在高噪声率问题中记住嘈杂标签的能力仍然是一个空旷的问题。最具竞争力的嘈杂标签学习算法依赖于一个2阶段的过程,其中包括无监督的学习,将培训样本分类为清洁或嘈杂,然后是半监督的学习,将经验仿生风险(EVR)最小化,该学习使用标记的集合制成的集合。样品被归类为干净,并提供了一个未标记的样品,该样品被分类为嘈杂。在本文中,我们假设这种2阶段嘈杂标签的学习方法的概括取决于无监督分类器的精度以及训练设置的大小以最大程度地减少EVR。我们从经验上验证了这两个假设,并提出了新的2阶段嘈杂标签训练算法longRemix。我们在嘈杂的标签基准CIFAR-10,CIFAR-100,Webvision,Clotsing1m和Food101-N上测试Longremix。结果表明,我们的Longremix比竞争方法更好,尤其是在高标签噪声问题中。此外,我们的方法在大多数数据集中都能达到最先进的性能。该代码可在https://github.com/filipe-research/longremix上获得。
translated by 谷歌翻译
自数据注释(尤其是对于大型数据集)以来,使用嘈杂的标签学习引起了很大的研究兴趣,这可能不可避免地不可避免。最近的方法通过将培训样本分为清洁和嘈杂的集合来求助于半监督的学习问题。然而,这种范式在重标签噪声下容易出现重大变性,因为干净样品的数量太小,无法进行常规方法。在本文中,我们介绍了一个新颖的框架,称为LC-Booster,以在极端噪音下明确处理学习。 LC-Booster的核心思想是将标签校正纳入样品选择中,以便可以通过可靠的标签校正来培训更纯化的样品,从而减轻确认偏差。实验表明,LC-Booster在几个嘈杂标签的基准测试中提高了最先进的结果,包括CIFAR-10,CIFAR-100,CLASTINGING 1M和WEBVISION。值得注意的是,在极端的90 \%噪声比下,LC-Booster在CIFAR-10和CIFAR-100上获得了92.9 \%和48.4 \%的精度,超过了最终方法,较大的边距就超过了最终方法。
translated by 谷歌翻译
带有嘈杂标签的训练深神经网络(DNN)实际上是具有挑战性的,因为不准确的标签严重降低了DNN的概括能力。以前的努力倾向于通过识别带有粗糙的小损失标准来减轻嘈杂标签的干扰的嘈杂数据来处理统一的denoising流中的零件或完整数据,而忽略了嘈杂样本的困难是不同的,因此是刚性和统一的。数据选择管道无法很好地解决此问题。在本文中,我们首先提出了一种称为CREMA的粗到精细的稳健学习方法,以分裂和串扰的方式处理嘈杂的数据。在粗糙水平中,干净和嘈杂的集合首先从统计意义上就可信度分开。由于实际上不可能正确对所有嘈杂样本进行分类,因此我们通过对每个样本的可信度进行建模来进一步处理它们。具体而言,对于清洁集,我们故意设计了一种基于内存的调制方案,以动态调整每个样本在训练过程中的历史可信度顺序方面的贡献,从而减轻了错误地分组为清洁集中的嘈杂样本的效果。同时,对于分类为嘈杂集的样品,提出了选择性标签更新策略,以纠正嘈杂的标签,同时减轻校正错误的问题。广泛的实验是基于不同方式的基准,包括图像分类(CIFAR,Clothing1M等)和文本识别(IMDB),具有合成或自然语义噪声,表明CREMA的优势和普遍性。
translated by 谷歌翻译
深神经网络(DNN)的记忆效应在最近的标签噪声学习方法中起关键作用。为了利用这种效果,已经广泛采用了基于模型预测的方法,该方法旨在利用DNN在学习的早期阶段以纠正嘈杂标签的效果。但是,我们观察到该模型在标签预测期间会犯错误,从而导致性能不令人满意。相比之下,在学习早期阶段产生的特征表现出更好的鲁棒性。受到这一观察的启发,在本文中,我们提出了一种基于特征嵌入的新方法,用于用标签噪声,称为标签NoissiLution(Lend)。要具体而言,我们首先根据当前的嵌入式特征计算一个相似性矩阵,以捕获训练数据的局部结构。然后,附近标记的数据(\ textIt {i.e。},标签噪声稀释)使错误标记的数据携带的嘈杂的监督信号淹没了,其有效性是由特征嵌入的固有鲁棒性保证的。最后,带有稀释标签的培训数据进一步用于培训强大的分类器。从经验上讲,我们通过将我们的贷款与几种代表性的强大学习方法进行比较,对合成和现实世界嘈杂数据集进行了广泛的实验。结果验证了我们贷款的有效性。
translated by 谷歌翻译
在标签 - 噪声学习中,估计过渡矩阵是一个热门话题,因为矩阵在构建统计上一致的分类器中起着重要作用。传统上,从干净的标签到嘈杂的标签(即,清洁标签过渡矩阵(CLTM))已被广泛利用,以通过使用嘈杂的数据来学习干净的标签分类器。该分类器的动机主要是输出贝叶斯的最佳预测标签,在本文中,我们研究以直接建模从贝叶斯最佳标签过渡到嘈杂标签(即贝叶斯标签,贝叶斯标签,是BLTM)),并学习分类器以预测贝叶斯最佳的分类器标签。请注意,只有嘈杂的数据,它不足以估计CLTM或BLTM。但是,贝叶斯最佳标签与干净标签相比,贝叶斯最佳标签的不确定性较小,即,贝叶斯最佳标签的类后代是一热矢量,而干净标签的载体则不是。这使两个优点能够估算BLTM,即(a)一组具有理论上保证的贝叶斯最佳标签的示例可以从嘈杂的数据中收集; (b)可行的解决方案空间要小得多。通过利用优势,我们通过采用深层神经网络来估计BLTM参数,从而更好地概括和出色的分类性能。
translated by 谷歌翻译
大型真实数据集中嘈杂的标签是不可避免的。在这项工作中,我们探索了以前的作品解读的一个区域 - 网络的架构如何影响其嘈杂标签的鲁棒性。我们提供一个正式的框架,将网络的稳健性连接到其架构和目标/噪声功能之间的对齐。我们的框架通过其表示中的预测力量来测量网络的稳健性 - 使用一小组清洁标签在学习的陈述上培训的线性模型的测试性能。我们假设网络对嘈杂标签更强大,如果其架构与目标功能比噪声更加对齐。为了支持我们的假设,我们提供各种神经网络架构和不同域的理论和经验证据。我们还发现,当网络与目标函数良好对齐时,在测试精度和甚至优于特勤方面的方法方面,它在最先进的(SOTA)噪声标签培训方法上的预测力可以提高。使用干净的标签。
translated by 谷歌翻译
Deep Neural Networks (DNNs) have been shown to be susceptible to memorization or overfitting in the presence of noisily-labelled data. For the problem of robust learning under such noisy data, several algorithms have been proposed. A prominent class of algorithms rely on sample selection strategies wherein, essentially, a fraction of samples with loss values below a certain threshold are selected for training. These algorithms are sensitive to such thresholds, and it is difficult to fix or learn these thresholds. Often, these algorithms also require information such as label noise rates which are typically unavailable in practice. In this paper, we propose an adaptive sample selection strategy that relies only on batch statistics of a given mini-batch to provide robustness against label noise. The algorithm does not have any additional hyperparameters for sample selection, does not need any information on noise rates and does not need access to separate data with clean labels. We empirically demonstrate the effectiveness of our algorithm on benchmark datasets.
translated by 谷歌翻译