人和车辆轨迹体现了运输基础设施的重要信息,轨迹相似性计算是许多涉及轨迹数据分析的现实世界应用中的功能。最近,基于深度学习的轨迹相似性技术使得能够提高传统相似性技术提高效率和适应性。然而,现有的轨迹相似度学习提案强调了时间相似性的空间相似性,使得它们次开用于时光分析。为此,我们提出了ST2VEC,这是一种基于轨迹表示的学习架构,其考虑了道路网络中的时空相似度学习的对轨迹对之间的细粒度的空间和时间相关性。据我们所知,这是第一个用于时空轨迹相似性分析的深学习建议。具体而言,ST2VEC包含三个阶段:(i)培训选择代表性培训样本的数据准备; (ii)设计轨迹的空间和时间建模,其中设计了通用时间建模模块(TMM)的轨迹的空间和时间特征; (iii)时空共关节融合(STCF),其中开发了统一的融合(UF)方法,以帮助产生统一的时空轨迹嵌入,以捕获轨迹之间的时空相似关系。此外,由课程概念启发,ST2VEC采用课程学习进行模型优化,以提高融合和有效性。实验研究提供了证据表明,ST2VEC显着胜过了所有最先进的竞争对手,在有效性,效率和可扩展性方面,同时显示出低参数敏感性和良好的模型稳健性。
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嘈杂的标签损坏了深网络的性能。为了稳健的学习,突出的两级管道在消除可能的不正确标签和半监督培训之间交替。然而,丢弃观察到的标签的部分可能导致信息丢失,尤其是当腐败不是完全随机的时,例如依赖类或实例依赖。此外,从代表性两级方法Dividemix的训练动态,我们确定了确认偏置的统治:伪标签未能纠正相当大量的嘈杂标签,因此累积误差。为了充分利用观察到的标签和减轻错误的校正,我们提出了强大的标签翻新(鲁棒LR)-a新的混合方法,该方法集成了伪标签和置信度估计技术来翻新嘈杂的标签。我们表明我们的方法成功减轻了标签噪声和确认偏差的损害。结果,它跨数据集和噪声类型实现最先进的结果。例如,强大的LR在真实世界嘈杂的数据集网络VIVION上以前最好的绝对高度提高了4.5%的绝对顶级精度改进。
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随着大数据的爆炸性增加,培训机器学习(ML)模型成为计算密集型工作量,需要几天甚至几周。因此,重用已经训练的模型受到了受关注的,称为转移学习。转移学习避免通过将知识从源任务转移到目标任务来避免从头开始培训新模型。现有的传输学习方法主要专注于如何通过特定源模型提高目标任务的性能,并假设给出了源模型。虽然有许多源模型可用,但数据科学家难以手动选择目标任务的最佳源模型。因此,如何在模型数据库中有效地选择合适的源模型进行模型重用是一个有趣但未解决的问题。在本文中,我们提出了SMS,有效,高效,灵活的源模型选择框架。即使源数据集具有明显不同的数据标签,SMS也是有效的,并且灵活地支持具有任何类型的结构的源模型,并且有效地避免任何培训过程。对于每个源模型,SMS首先将目标数据集中的样本加速到软标签中,通过直接将该模型直接应用于目标数据集,然后使用高斯分布适合软标签的集群,最后测量源模型使用的显着能力高斯混合的公制。此外,我们提出了一种改进的SMS(I-SMS),其降低了源模型的输出数量。 I-SMS可以显着降低选择时间,同时保留SMS的选择性能。关于一系列实用模型重用工作负载的广泛实验证明了SMS的有效性和效率。
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A key feature of federated learning (FL) is to preserve the data privacy of end users. However, there still exist potential privacy leakage in exchanging gradients under FL. As a result, recent research often explores the differential privacy (DP) approaches to add noises to the computing results to address privacy concerns with low overheads, which however degrade the model performance. In this paper, we strike the balance of data privacy and efficiency by utilizing the pervasive social connections between users. Specifically, we propose SCFL, a novel Social-aware Clustered Federated Learning scheme, where mutually trusted individuals can freely form a social cluster and aggregate their raw model updates (e.g., gradients) inside each cluster before uploading to the cloud for global aggregation. By mixing model updates in a social group, adversaries can only eavesdrop the social-layer combined results, but not the privacy of individuals. We unfold the design of SCFL in three steps. \emph{i) Stable social cluster formation. Considering users' heterogeneous training samples and data distributions, we formulate the optimal social cluster formation problem as a federation game and devise a fair revenue allocation mechanism to resist free-riders. ii) Differentiated trust-privacy mapping}. For the clusters with low mutual trust, we design a customizable privacy preservation mechanism to adaptively sanitize participants' model updates depending on social trust degrees. iii) Distributed convergence}. A distributed two-sided matching algorithm is devised to attain an optimized disjoint partition with Nash-stable convergence. Experiments on Facebook network and MNIST/CIFAR-10 datasets validate that our SCFL can effectively enhance learning utility, improve user payoff, and enforce customizable privacy protection.
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As language models (LMs) scale, they develop many novel behaviors, good and bad, exacerbating the need to evaluate how they behave. Prior work creates evaluations with crowdwork (which is time-consuming and expensive) or existing data sources (which are not always available). Here, we automatically generate evaluations with LMs. We explore approaches with varying amounts of human effort, from instructing LMs to write yes/no questions to making complex Winogender schemas with multiple stages of LM-based generation and filtering. Crowdworkers rate the examples as highly relevant and agree with 90-100% of labels, sometimes more so than corresponding human-written datasets. We generate 154 datasets and discover new cases of inverse scaling where LMs get worse with size. Larger LMs repeat back a dialog user's preferred answer ("sycophancy") and express greater desire to pursue concerning goals like resource acquisition and goal preservation. We also find some of the first examples of inverse scaling in RL from Human Feedback (RLHF), where more RLHF makes LMs worse. For example, RLHF makes LMs express stronger political views (on gun rights and immigration) and a greater desire to avoid shut down. Overall, LM-written evaluations are high-quality and let us quickly discover many novel LM behaviors.
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As AI systems become more capable, we would like to enlist their help to supervise other AIs. We experiment with methods for training a harmless AI assistant through self-improvement, without any human labels identifying harmful outputs. The only human oversight is provided through a list of rules or principles, and so we refer to the method as 'Constitutional AI'. The process involves both a supervised learning and a reinforcement learning phase. In the supervised phase we sample from an initial model, then generate self-critiques and revisions, and then finetune the original model on revised responses. In the RL phase, we sample from the finetuned model, use a model to evaluate which of the two samples is better, and then train a preference model from this dataset of AI preferences. We then train with RL using the preference model as the reward signal, i.e. we use 'RL from AI Feedback' (RLAIF). As a result we are able to train a harmless but non-evasive AI assistant that engages with harmful queries by explaining its objections to them. Both the SL and RL methods can leverage chain-of-thought style reasoning to improve the human-judged performance and transparency of AI decision making. These methods make it possible to control AI behavior more precisely and with far fewer human labels.
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Developing safe and useful general-purpose AI systems will require us to make progress on scalable oversight: the problem of supervising systems that potentially outperform us on most skills relevant to the task at hand. Empirical work on this problem is not straightforward, since we do not yet have systems that broadly exceed our abilities. This paper discusses one of the major ways we think about this problem, with a focus on how to turn it into one that can be productively studied empirically. We first present an experimental design centered on choosing tasks for which human specialists succeed but unaided humans and current general AI systems fail. We then present a proof-of-concept experiment following meant to demonstrate a key feature of this experimental design and show its viability with two question-answering tasks: MMLU and time-limited QuALITY. On these tasks, we find that human participants who interact with an unreliable large-language-model dialog assistant through chat -- a trivial baseline strategy for scalable oversight -- substantially outperform both the model alone and their own unaided performance. These results are an encouraging sign that scalable oversight will be tractable to study with present models and bolster recent findings that large language models can productively assist humans with difficult tasks.
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“感应头”是注意力头,它实现了一种简单的算法来完成令牌序列,例如[a] [b] ... [a] - > [b]。在这项工作中,我们提供了一个假设的初步和间接证据,即诱导头可能构成大型大型变压器模型中所有“文本学习”中大多数的机制(即减少在增加代币指数时损失的损失)。我们发现,诱导头在与秘密学习能力突然急剧上的急剧上升的位置完全相同,这是训练损失的颠簸。我们提出了六种互补的证据,认为诱导头可能是任何大小的变压器模型中一般性内部学习的机理来源。对于仅关注的小型模型,我们提供了有力的因果证据。对于具有MLP的较大模型,我们提供相关证据。
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模块化设计是未来大型空间设施的On On On构造技术的基础。标准界面是未来空间机器人系统和空间设施模块化设计的关键技术。本文介绍了Petlock的设计和测试,标准和测试无性别界面可以在未来的模块化空间机器人操纵器和航天器之间传递机械载荷,功率和数据。Petlock采用完全无性别的设计,包括连接面,锁定机制,数据和功率接口。连接表面提供了较大的翻译和旋转错位耐受性,由于其120度对称和3D形状的设计。锁定机制具有三个锁定引脚撤回结构设计,这是简单可靠的。高锁定力,高容忍度,高可靠性和低成本的优势,Petloc K在未来的轨道施工任务中具有很大的应用潜力。
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向前和向后触及逆运动学(FABRIK)是一种启发式逆运动求解器,逐渐应用于具有快速收敛和生成更真实配置的优势的操纵器。但是,在高误差限制下,Fabrik表现出不稳定的收敛行为,这对于操纵器的实时运动计划是不满意的。在本文中,提出了一种结合Fabrik和顺序二次编程(SQP)算法的新型逆运动学算法,其中Fabrik推迟的关节角度将被视为SQP算法的初始种子,以避免粘在局部最小值中。通过实验评估合并的算法,在高误差约束下,我们的算法比FabRik获得更高的成功率和更快的解决方案时间。此外,联合算法可以在路径跟踪中为UR5和KUKA LBR IIWA 14 R820操纵器生成连续轨迹,而无姿势误差和最终效应器的允许位置误差。
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