联合学习(FL)是机器学习的一个子领域,在该子机学习中,多个客户试图在通信约束下通过网络进行协作学习模型。我们考虑在二阶功能相似性条件和强凸度下联合优化的有限和联合优化,并提出了两种新算法:SVRP和催化的SVRP。这种二阶相似性条件最近越来越流行,并且在包括分布式统计学习和差异性经验风险最小化在内的许多应用中得到满足。第一种算法SVRP结合了近似随机点评估,客户采样和降低方差。我们表明,当功能相似性足够高时,SVRP是沟通有效的,并且在许多现有算法上取得了卓越的性能。我们的第二个算法,催化的SVRP,是SVRP的催化剂加速变体,在二阶相似性和强凸度下,现有的联合优化算法可实现更好的性能,并均匀地改善了现有的算法。在分析这些算法的过程中,我们提供了可能具有独立关注的随机近端方法(SPPM)的新分析。我们对SPPM的分析很简单,允许进行近似近端评估,不需要任何平滑度假设,并且在通信复杂性上比普通分布式随机梯度下降显示出明显的好处。
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肝脏是脊椎动物中最关键的代谢器官之一,由于其在人体中的重要功能,例如废物产物和药物的血液排毒。由于肝肿瘤引起的肝病是全球最常见的死亡率之一。因此,在肿瘤发育的早期阶段检测肝肿瘤是医疗治疗的关键部分。许多成像方式可以用作检测肝肿瘤的帮助工具。计算机断层扫描(CT)是软组织器官(例如肝脏)最常用的成像方式。这是因为它是一种侵入性方式,可以相对迅速捕获。本文提出了一个有效的自动肝分割框架,以使用3D CNN深度元网络模型检测和分割肝脏腹部扫描。许多研究采用了精确分割肝区域,然后使用分割的肝区域作为肿瘤分割方法的输入,因为它降低了由于将腹部器官分割为肿瘤而导致的错误率。所提出的3D CNN DeepMedic模型具有两个输入途径,而不是一个途径,如原始3D CNN模型所示。在本文中,该网络提供了多个腹部CT版本,这有助于提高细分质量。提出的模型分别达到94.36%,94.57%,91.86%和93.14%的精度,灵敏度,特异性和骰子相似性得分。实验结果表明该方法的适用性。
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梯度压缩是一种流行的技术,可改善机器学习模型分布式培训中随机一阶方法的沟通复杂性。但是,现有作品仅考虑随机梯度的替换采样。相比之下,在实践中众所周知,最近从理论上证实,基于没有替代抽样的随机方法,例如随机改组方法(RR)方法,其性能要比用更换梯度进行梯度的方法更好。在这项工作中,我们在文献中缩小了这一差距,并通过梯度压缩和没有替代抽样的方法提供了第一次分析方法。我们首先使用梯度压缩(Q-RR)开发一个随机重新填充的分布式变体,并展示如何通过使用控制迭代来减少梯度量化的方差。接下来,为了更好地适合联合学习应用程序,我们结合了本地计算,并提出了一种称为Q-Nastya的Q-RR的变体。 Q-Nastya使用本地梯度步骤以及不同的本地和全球步骤。接下来,我们还展示了如何在此设置中减少压缩差异。最后,我们证明了所提出的方法的收敛结果,并概述了它们在现有算法上改进的几种设置。
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预测道路用户的未来行为是自主驾驶中最具挑战性和最重要的问题之一。应用深度学习对此问题需要以丰富的感知信号和地图信息的形式融合异构世界状态,并在可能的期货上推断出高度多模态分布。在本文中,我们呈现MultiPath ++,这是一个未来的预测模型,实现了在流行的基准上实现最先进的性能。 MultiPath ++通过重新访问许多设计选择来改善多径架构。第一关键设计差异是偏离基于图像的基于输入世界状态的偏离,有利于异构场景元素的稀疏编码:多径++消耗紧凑且有效的折线,直接描述道路特征和原始代理状态信息(例如,位置,速度,加速)。我们提出了一种背景感知这些元素的融合,并开发可重用的多上下文选通融合组件。其次,我们重新考虑了预定义,静态锚点的选择,并开发了一种学习模型端到端的潜在锚嵌入的方法。最后,我们在其他ML域中探索合奏和输出聚合技术 - 常见的常见域 - 并为我们的概率多模式输出表示找到有效的变体。我们对这些设计选择进行了广泛的消融,并表明我们所提出的模型在协会运动预测竞争和Waymo开放数据集运动预测挑战上实现了最先进的性能。
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联邦学习(FL)是一种越来越受欢迎的机器学习范式,其中多个节点在隐私,通信和多个异质性约束下尝试协同学习。联邦学习中的持续存在问题是,不清楚优化目标应该:监督学习的标准平均风险最小化在处理联合学习的几个主要限制方面是不充分的,例如沟通适应性和个性化控制。我们在联合学习的框架中识别几个关键的Desiderata,并介绍了一个新的框架,Flix,考虑到联合学习所带来的独特挑战。 Flix具有标准的有限和形式,使从业者能够利用分布式优化的现有(潜在非本地)方法的巨大财富。通过不需要任何通信的智能初始化,Flix不需要使用本地步骤,但仍然可以通过本地方法执行不一致的正则化。我们提供了几种用于在通信约束下有效解决FLIX制剂的算法。最后,我们通过广泛的实验证实了我们的理论结果。
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We provide a new analysis of local SGD, removing unnecessary assumptions and elaborating on the difference between two data regimes: identical and heterogeneous. In both cases, we improve the existing theory and provide values of the optimal stepsize and optimal number of local iterations. Our bounds are based on a new notion of variance that is specific to local SGD methods with different data. The tightness of our results is guaranteed by recovering known statements when we plug H " 1, where H is the number of local steps. The empirical evidence further validates the severe impact of data heterogeneity on the performance of local SGD.
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The performance of the Deep Learning (DL) models depends on the quality of labels. In some areas, the involvement of human annotators may lead to noise in the data. When these corrupted labels are blindly regarded as the ground truth (GT), DL models suffer from performance deficiency. This paper presents a method that aims to learn a confident model in the presence of noisy labels. This is done in conjunction with estimating the uncertainty of multiple annotators. We robustly estimate the predictions given only the noisy labels by adding entropy or information-based regularizer to the classifier network. We conduct our experiments on a noisy version of MNIST, CIFAR-10, and FMNIST datasets. Our empirical results demonstrate the robustness of our method as it outperforms or performs comparably to other state-of-the-art (SOTA) methods. In addition, we evaluated the proposed method on the curated dataset, where the noise type and level of various annotators depend on the input image style. We show that our approach performs well and is adept at learning annotators' confusion. Moreover, we demonstrate how our model is more confident in predicting GT than other baselines. Finally, we assess our approach for segmentation problem and showcase its effectiveness with experiments.
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Artificial Intelligence (AI) has become commonplace to solve routine everyday tasks. Because of the exponential growth in medical imaging data volume and complexity, the workload on radiologists is steadily increasing. We project that the gap between the number of imaging exams and the number of expert radiologist readers required to cover this increase will continue to expand, consequently introducing a demand for AI-based tools that improve the efficiency with which radiologists can comfortably interpret these exams. AI has been shown to improve efficiency in medical-image generation, processing, and interpretation, and a variety of such AI models have been developed across research labs worldwide. However, very few of these, if any, find their way into routine clinical use, a discrepancy that reflects the divide between AI research and successful AI translation. To address the barrier to clinical deployment, we have formed MONAI Consortium, an open-source community which is building standards for AI deployment in healthcare institutions, and developing tools and infrastructure to facilitate their implementation. This report represents several years of weekly discussions and hands-on problem solving experience by groups of industry experts and clinicians in the MONAI Consortium. We identify barriers between AI-model development in research labs and subsequent clinical deployment and propose solutions. Our report provides guidance on processes which take an imaging AI model from development to clinical implementation in a healthcare institution. We discuss various AI integration points in a clinical Radiology workflow. We also present a taxonomy of Radiology AI use-cases. Through this report, we intend to educate the stakeholders in healthcare and AI (AI researchers, radiologists, imaging informaticists, and regulators) about cross-disciplinary challenges and possible solutions.
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Recent advances in upper limb prostheses have led to significant improvements in the number of movements provided by the robotic limb. However, the method for controlling multiple degrees of freedom via user-generated signals remains challenging. To address this issue, various machine learning controllers have been developed to better predict movement intent. As these controllers become more intelligent and take on more autonomy in the system, the traditional approach of representing the human-machine interface as a human controlling a tool becomes limiting. One possible approach to improve the understanding of these interfaces is to model them as collaborative, multi-agent systems through the lens of joint action. The field of joint action has been commonly applied to two human partners who are trying to work jointly together to achieve a task, such as singing or moving a table together, by effecting coordinated change in their shared environment. In this work, we compare different prosthesis controllers (proportional electromyography with sequential switching, pattern recognition, and adaptive switching) in terms of how they present the hallmarks of joint action. The results of the comparison lead to a new perspective for understanding how existing myoelectric systems relate to each other, along with recommendations for how to improve these systems by increasing the collaborative communication between each partner.
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Nowadays, the current neural network models of dialogue generation(chatbots) show great promise for generating answers for chatty agents. But they are short-sighted in that they predict utterances one at a time while disregarding their impact on future outcomes. Modelling a dialogue's future direction is critical for generating coherent, interesting dialogues, a need that has led traditional NLP dialogue models that rely on reinforcement learning. In this article, we explain how to combine these objectives by using deep reinforcement learning to predict future rewards in chatbot dialogue. The model simulates conversations between two virtual agents, with policy gradient methods used to reward sequences that exhibit three useful conversational characteristics: the flow of informality, coherence, and simplicity of response (related to forward-looking function). We assess our model based on its diversity, length, and complexity with regard to humans. In dialogue simulation, evaluations demonstrated that the proposed model generates more interactive responses and encourages a more sustained successful conversation. This work commemorates a preliminary step toward developing a neural conversational model based on the long-term success of dialogues.
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