我们考虑一个矩阵完成问题,用于将社交或项目相似性图形作为侧面信息。我们开发了一种普遍的,无参数和计算的有效算法,该算法以分层图形聚类开始,然后迭代地改进图形聚类和矩阵额定值。在一个层次的随机块模型,尊重实际相关的社交图和低秩评级矩阵模型(要详细),我们证明了我们的算法实现了观察到的矩阵条目数量的信息 - 理论限制(即,最佳通过与较低的不可能结果一起导出的样本复杂性)通过最大似然估计。该结果的一个结果是利用社交图的层次结构,相对于简单地识别不同组的情况,在不诉诸于它们的情况下,可以产生相对于不同组的样本复杂性的大量增益。我们对合成和现实世界数据集进行了广泛的实验,以证实我们的理论结果,并展示了利用图形侧信息的其他矩阵完成算法的显着性能改进。
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Online personalized recommendation services are generally hosted in the cloud where users query the cloud-based model to receive recommended input such as merchandise of interest or news feed. State-of-the-art recommendation models rely on sparse and dense features to represent users' profile information and the items they interact with. Although sparse features account for 99% of the total model size, there was not enough attention paid to the potential information leakage through sparse features. These sparse features are employed to track users' behavior, e.g., their click history, object interactions, etc., potentially carrying each user's private information. Sparse features are represented as learned embedding vectors that are stored in large tables, and personalized recommendation is performed by using a specific user's sparse feature to index through the tables. Even with recently-proposed methods that hides the computation happening in the cloud, an attacker in the cloud may be able to still track the access patterns to the embedding tables. This paper explores the private information that may be learned by tracking a recommendation model's sparse feature access patterns. We first characterize the types of attacks that can be carried out on sparse features in recommendation models in an untrusted cloud, followed by a demonstration of how each of these attacks leads to extracting users' private information or tracking users by their behavior over time.
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The recent advent of play-to-earn (P2E) systems in massively multiplayer online role-playing games (MMORPGs) has made in-game goods interchangeable with real-world values more than ever before. The goods in the P2E MMORPGs can be directly exchanged with cryptocurrencies such as Bitcoin, Ethereum, or Klaytn via blockchain networks. Unlike traditional in-game goods, once they had been written to the blockchains, P2E goods cannot be restored by the game operation teams even with chargeback fraud such as payment fraud, cancellation, or refund. To tackle the problem, we propose a novel chargeback fraud prediction method, PU GNN, which leverages graph attention networks with PU loss to capture both the players' in-game behavior with P2E token transaction patterns. With the adoption of modified GraphSMOTE, the proposed model handles the imbalanced distribution of labels in chargeback fraud datasets. The conducted experiments on two real-world P2E MMORPG datasets demonstrate that PU GNN achieves superior performances over previously suggested methods.
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在本文中,我们描述了RTZR团队Voxceleb扬声器识别挑战2022(VOXSRC-22)的最高得分提交,在封闭的数据集中,扬声器验证轨道1.最高执行的系统是7型型号的融合,其中包含3种不同类型的类型模型体系结构。我们专注于培训模型以学习周期性信息。因此,所有型号均以4-6秒的镜头训练,每次发言。此外,我们采用了较大的保证金微调策略,该策略在我们的某些融合模型的先前挑战上表现出良好的表现。在评估过程中,我们应用了具有自适应对称归一化(AS-NORM)和矩阵得分平均值(MSA)的评分方法。最后,我们将模型与逻辑回归混合在一起,以融合所有受过训练的模型。最终提交在VOXSRC22测试集上实现了0.165 DCF和2.912%EER。
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拆分学习和推理建议运行跨客户设备和云的大型模型的培训/推理。但是,这样的模型拆分引起了隐私问题,因为流过拆分层的激活可能会泄漏有关客户端私人输入数据的信息。当前,没有一个好方法可以量化通过分层泄漏多少私人信息,也没有一种将隐私提高到所需级别的好方法。在这项工作中,我们建议将Fisher信息用作隐私指标来衡量和控制信息泄漏。我们表明,Fisher信息可以直观地理解以无偏重建攻击者的限制的错误形式通过拆分层泄漏了多少私人信息。然后,我们提出了一种增强隐私的技术REFIL,可以在拆分层上强制使用用户呈现的Fisher信息泄漏,以实现高隐私,同时保持合理的实用程序。
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Wearable sensor-based human activity recognition (HAR) has emerged as a principal research area and is utilized in a variety of applications. Recently, deep learning-based methods have achieved significant improvement in the HAR field with the development of human-computer interaction applications. However, they are limited to operating in a local neighborhood in the process of a standard convolution neural network, and correlations between different sensors on body positions are ignored. In addition, they still face significant challenging problems with performance degradation due to large gaps in the distribution of training and test data, and behavioral differences between subjects. In this work, we propose a novel Transformer-based Adversarial learning framework for human activity recognition using wearable sensors via Self-KnowledgE Distillation (TASKED), that accounts for individual sensor orientations and spatial and temporal features. The proposed method is capable of learning cross-domain embedding feature representations from multiple subjects datasets using adversarial learning and the maximum mean discrepancy (MMD) regularization to align the data distribution over multiple domains. In the proposed method, we adopt the teacher-free self-knowledge distillation to improve the stability of the training procedure and the performance of human activity recognition. Experimental results show that TASKED not only outperforms state-of-the-art methods on the four real-world public HAR datasets (alone or combined) but also improves the subject generalization effectively.
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联合学习(FL)旨在对多个数据所有者持有的分布式数据执行隐私的机器学习。为此,FL要求数据所有者在本地执行培训,并与中央服务器共享梯度更新(而不是私人输入),然后将其安全地汇总在多个数据所有者上。尽管汇总本身并不能证明提供隐私保护,但先前的工作表明,如果批处理大小足够大,则足够了。在本文中,我们提出了鸡尾酒会攻击(CPA),与先前的信念相反,能够从汇总的渐变中恢复私人输入,这是批量较大的大小。 CPA利用了至关重要的见解,即来自完全连接的层的总梯度是其输入的线性组合,这使我们将梯度反演作为盲源分离(BSS)问题(非正式地称为鸡尾酒会问题)。我们适应独立的组件分析(ICA) - BSS问题的经典解决方案 - 恢复针对完全连接和卷积网络的私人输入,并表明CPA明显优于先前的梯度反转攻击,对成像网的输入量表,并表现出Imagenet大小的输入的范围最高可达1024的大批量。
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增强学习(RL)在接触式操纵中的经验成功(RL)从基于模型的角度来理解了很多待理解,其中关键困难通常归因于(i)触点模式的爆炸,(ii)僵硬,非平滑接触动力学和由此产生的爆炸 /不连续梯度,以及(iii)计划问题的非转换性。 RL的随机性质通过有效采样和平均接触模式来解决(i)和(ii)。另一方面,基于模型的方法通过分析平滑接触动力学来解决相同的挑战。我们的第一个贡献是建立两种方法的简单系统方法的理论等效性,并在许多复杂示例上提供定性和经验的等效性。为了进一步减轻(II),我们的第二个贡献是凸面的凸面,可区分和准动力的触点动力学表述,这两个方案都可以平滑方案,并且通过实验证明了对接触富含接触的计划非常有效。我们的最终贡献解决了(III),在其中我们表明,当通过平滑度抽取接触模式时,基于经典的运动计划算法在全球计划中可以有效。将我们的方法应用于具有挑战性的接触式操纵任务的集合中,我们证明了基于模型的有效运动计划可以实现与RL相当的结果,而计算却大大较少。视频:https://youtu.be/12ew4xc-vwa
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近年来,Experts(MOE)的混合物已成为一种有前途的深度学习技术,可以将模型能力扩展为万亿多个参数,同时通过稀疏计算降低计算成本。虽然MoE开设了一个非常大的模型的新领域,但由于MOE的动态性质与系统的静态平行性/管道层之间的不匹配,因此其数以千计的GPU的实现受到限制。我们提出了Tutel,这是一种具有动态自适应并行性和管道的高度可扩展的堆栈设计和实现。 TUTEL在运行时提供自适应并行性切换和自适应管道,分别达到1.74倍和2.00倍的单MOE层加速度。我们还提出了一种用于MOE通信速度的新颖的二维层次结构算法,该算法的表现超过了2,048 GPU的先前最先前的最新时间。 Tutel汇总了所有技术,最终在16 GPU和2,048 GPU上分别提供了4.96倍和5.75倍的加速度,分别通过Fairseq:Meta的Facebook AI AI研究序列到序列工具Kit(Tutel(Tutel)(Tutel)(Tutel)(现在由Fairseq部分采用)。 Tutel源代码可在公共场所获得:https://github.com/microsoft/tutel。我们的评估表明,Tutel有效,有效地运行了一个基于现实的MOE模型,名为Swinv2-Moe,建立在Swin Transformer V2上,这是一种最先进的计算机视觉体系结构。在效率方面,Tutel加速了Swinv2-MoE,在FairSeq的训练和推理中分别达到1.55倍和2.11倍的速度。关于有效性,SWINV2-MOE模型在预训练和下游计算机视觉任务(例如可可对象检测)方面都比对应的密度密度模型都达到了卓越的精度,这表明Tutel准备对端到端现实世界模型训练的准备就绪和推理。 Swinv2-Moe在https://github.com/microsoft/swin-transformer中开放。
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我们介绍了一个名为统计信息的神经网络(SINN)的机器学习框架,用于从数据中学习随机动力学。从理论上讲,这种新的架构是受到随机系统的通用近似定理的启发,我们在本文中介绍了它,以及用于随机建模的投影手术形式。我们设计了训练神经网络模型的机制,以重现目标随机过程的正确\ emph {统计}行为。数值模拟结果表明,受过良好训练的SINN可以可靠地近似马尔可夫和非马克维亚随机动力学。我们证明了SINN对粗粒问题和过渡动力学的建模的适用性。此外,我们表明可以在时间粗粒的数据上训练所获得的减少阶模型,因此非常适合稀有事实模拟。
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