异常检测旨在识别正常数据分布的偏差样本。对比学习提供了一种成功的样本表示方式,可以有效地歧视异常。但是,当在半监督环境下设置的训练中被未标记的异常样本污染时,当前基于对比的方法通常1)忽略训练数据之间的全面关系,导致次优的性能,2)需要微调,导致低效率的低效率。为了解决上述两个问题,在本文中,我们提出了一种新型的分层半监督对比学习(HSCL)框架,以抗污染异常检测。具体而言,HSCL分层调节了三个互补关系:样本到样本,样本到原型型和正常关系,通过对受污染数据的全面探索,扩大了正常样本和异常样本之间的歧视。此外,HSCL是一种端到端的学习方法,可以在不进行微调的情况下有效地学习判别性表示。 HSCL在多种方案中实现了最先进的性能,例如单级分类和跨数据库检测。广泛的消融研究进一步验证了每个考虑的关系的有效性。该代码可在https://github.com/gaoangw/hscl上找到。
translated by 谷歌翻译
大型数据集对于深度学习模型的开发非常重要。此类数据集通常需要繁重的注释工作量,这是非常耗时和昂贵的。为了加速注释过程,可以采用多个注释器来标记数据的不同子集。但是,不同的注释器之间的不一致和偏差对模型培训有害,特别是对于定性和主观的任务。在本文中解决了这一挑战,我们提出了一种新的对比回归框架来解决每个样本的不相交的注释问题仅由一个注释器和多个注释器标记在数据的不相交子集上工作。要考虑到注释器内的一致性和间歇委员会间不一致,使用了两种策略。过度,应用基于对比的损失来学习相同注释者的不同样本之间的相对排名,假设排名来自相同注释器的样本是一致的。其次,我们应用渐变反转层以学习不变的稳健表示到不同的注释器。对面部表情预测任务的实验,以及图像质量评估任务,验证了我们提出的框架的有效性。
translated by 谷歌翻译
半监督学习(SSL)是一个有效的框架,可以使用标记和未标记的数据训练模型,但是当缺乏足够的标记样品时,可能会产生模棱两可和不可区分的表示。有了人类的循环学习,积极的学习可以迭代地选择无标记的样品进行标签和培训,以提高SSL框架的性能。但是,大多数现有的活跃学习方法都取决于预先训练的功能,这不适合端到端学习。为了解决SSL的缺点,在本文中,我们提出了一种新颖的端到端表示方法,即ActiveMatch,它将SSL与对比度学习和积极学习结合在一起,以充分利用有限的标签。从少量的标记数据开始,无监督的对比度学习作为热身学习,然后将ActiveMatch结合在一起,将SSL和监督对比度学习结合在一起,并积极选择在培训期间标记的最具代表性的样本,从而更好地表示分类。与MixMatch和FixMatch具有相同数量的标记数据相比,我们表明ActiveMatch实现了最先进的性能,CIFAR-10的精度为89.24%,具有100个收集的标签,而92.20%的精度为92.20%,有200个收集的标签。
translated by 谷歌翻译
与静态图像不同,视频包含其他时间和空间信息,以进行更好的对象检测。但是,获得大量带有有界框注释的视频是昂贵的,这些视频是有监督的深度学习所需的。尽管人类只能通过仅观看几个视频剪辑来轻松学习识别新对象,但深度学习通常会遭受过度拟合。这导致了一个重要的问题:如何仅从几个标记的视频剪辑中有效地学习视频对象探测器?在本文中,我们研究了视频对象检测几乎没有学习的新问题。我们首先定义了几个弹出设置,并创建一个新的基准数据集,以用于从广泛使用的Imagenet VID数据集中得出的几个弹片视频对象检测。我们采用转移学习框架来有效地训练视频对象探测器在大量基类对象和一些新颖级别对象的视频剪辑上。通过在我们设计的弱和强基数据集中分析该框架(关节和冻结)下两种方法的结果,我们揭示了不足和过度拟合问题。一种简单但有效的方法,称为融化,是自然开发的,可以权衡这两个问题并验证我们的分析。在我们提议的基准数据集上进行不同方案的广泛实验证明了我们在这个新的几弹视频对象检测问题中新颖分析的有效性。
translated by 谷歌翻译
In this paper, we propose a robust 3D detector, named Cross Modal Transformer (CMT), for end-to-end 3D multi-modal detection. Without explicit view transformation, CMT takes the image and point clouds tokens as inputs and directly outputs accurate 3D bounding boxes. The spatial alignment of multi-modal tokens is performed implicitly, by encoding the 3D points into multi-modal features. The core design of CMT is quite simple while its performance is impressive. CMT obtains 73.0% NDS on nuScenes benchmark. Moreover, CMT has a strong robustness even if the LiDAR is missing. Code will be released at https://github.com/junjie18/CMT.
translated by 谷歌翻译
Knowledge graphs (KG) have served as the key component of various natural language processing applications. Commonsense knowledge graphs (CKG) are a special type of KG, where entities and relations are composed of free-form text. However, previous works in KG completion and CKG completion suffer from long-tail relations and newly-added relations which do not have many know triples for training. In light of this, few-shot KG completion (FKGC), which requires the strengths of graph representation learning and few-shot learning, has been proposed to challenge the problem of limited annotated data. In this paper, we comprehensively survey previous attempts on such tasks in the form of a series of methods and applications. Specifically, we first introduce FKGC challenges, commonly used KGs, and CKGs. Then we systematically categorize and summarize existing works in terms of the type of KGs and the methods. Finally, we present applications of FKGC models on prediction tasks in different areas and share our thoughts on future research directions of FKGC.
translated by 谷歌翻译
Few Shot Instance Segmentation (FSIS) requires models to detect and segment novel classes with limited several support examples. In this work, we explore a simple yet unified solution for FSIS as well as its incremental variants, and introduce a new framework named Reference Twice (RefT) to fully explore the relationship between support/query features based on a Transformer-like framework. Our key insights are two folds: Firstly, with the aid of support masks, we can generate dynamic class centers more appropriately to re-weight query features. Secondly, we find that support object queries have already encoded key factors after base training. In this way, the query features can be enhanced twice from two aspects, i.e., feature-level and instance-level. In particular, we firstly design a mask-based dynamic weighting module to enhance support features and then propose to link object queries for better calibration via cross-attention. After the above steps, the novel classes can be improved significantly over our strong baseline. Additionally, our new framework can be easily extended to incremental FSIS with minor modification. When benchmarking results on the COCO dataset for FSIS, gFSIS, and iFSIS settings, our method achieves a competitive performance compared to existing approaches across different shots, e.g., we boost nAP by noticeable +8.2/+9.4 over the current state-of-the-art FSIS method for 10/30-shot. We further demonstrate the superiority of our approach on Few Shot Object Detection. Code and model will be available.
translated by 谷歌翻译
Graph Neural Networks (GNNs) have shown satisfying performance on various graph learning tasks. To achieve better fitting capability, most GNNs are with a large number of parameters, which makes these GNNs computationally expensive. Therefore, it is difficult to deploy them onto edge devices with scarce computational resources, e.g., mobile phones and wearable smart devices. Knowledge Distillation (KD) is a common solution to compress GNNs, where a light-weighted model (i.e., the student model) is encouraged to mimic the behavior of a computationally expensive GNN (i.e., the teacher GNN model). Nevertheless, most existing GNN-based KD methods lack fairness consideration. As a consequence, the student model usually inherits and even exaggerates the bias from the teacher GNN. To handle such a problem, we take initial steps towards fair knowledge distillation for GNNs. Specifically, we first formulate a novel problem of fair knowledge distillation for GNN-based teacher-student frameworks. Then we propose a principled framework named RELIANT to mitigate the bias exhibited by the student model. Notably, the design of RELIANT is decoupled from any specific teacher and student model structures, and thus can be easily adapted to various GNN-based KD frameworks. We perform extensive experiments on multiple real-world datasets, which corroborates that RELIANT achieves less biased GNN knowledge distillation while maintaining high prediction utility.
translated by 谷歌翻译
This paper focuses on designing efficient models with low parameters and FLOPs for dense predictions. Even though CNN-based lightweight methods have achieved stunning results after years of research, trading-off model accuracy and constrained resources still need further improvements. This work rethinks the essential unity of efficient Inverted Residual Block in MobileNetv2 and effective Transformer in ViT, inductively abstracting a general concept of Meta-Mobile Block, and we argue that the specific instantiation is very important to model performance though sharing the same framework. Motivated by this phenomenon, we deduce a simple yet efficient modern \textbf{I}nverted \textbf{R}esidual \textbf{M}obile \textbf{B}lock (iRMB) for mobile applications, which absorbs CNN-like efficiency to model short-distance dependency and Transformer-like dynamic modeling capability to learn long-distance interactions. Furthermore, we design a ResNet-like 4-phase \textbf{E}fficient \textbf{MO}del (EMO) based only on a series of iRMBs for dense applications. Massive experiments on ImageNet-1K, COCO2017, and ADE20K benchmarks demonstrate the superiority of our EMO over state-of-the-art methods, \eg, our EMO-1M/2M/5M achieve 71.5, 75.1, and 78.4 Top-1 that surpass \textbf{SoTA} CNN-/Transformer-based models, while trading-off the model accuracy and efficiency well.
translated by 谷歌翻译
The development of social media user stance detection and bot detection methods rely heavily on large-scale and high-quality benchmarks. However, in addition to low annotation quality, existing benchmarks generally have incomplete user relationships, suppressing graph-based account detection research. To address these issues, we propose a Multi-Relational Graph-Based Twitter Account Detection Benchmark (MGTAB), the first standardized graph-based benchmark for account detection. To our knowledge, MGTAB was built based on the largest original data in the field, with over 1.55 million users and 130 million tweets. MGTAB contains 10,199 expert-annotated users and 7 types of relationships, ensuring high-quality annotation and diversified relations. In MGTAB, we extracted the 20 user property features with the greatest information gain and user tweet features as the user features. In addition, we performed a thorough evaluation of MGTAB and other public datasets. Our experiments found that graph-based approaches are generally more effective than feature-based approaches and perform better when introducing multiple relations. By analyzing experiment results, we identify effective approaches for account detection and provide potential future research directions in this field. Our benchmark and standardized evaluation procedures are freely available at: https://github.com/GraphDetec/MGTAB.
translated by 谷歌翻译