我们表明,如果基于深度学习的插值器使用球形线性插值器作为基线,可以更准确,有效地求解在一组关键帧上进行人类运动的任务。我们从经验上证明了我们在实现最新性能的公开数据集上的方法的实力。我们通过证明$ \ delta $ - 优势相对于最后已知帧(也称为零速度模型)的参考,进一步概括了这些结果。这支持了一个更一般的结论,即在参考框架本地对输入帧的工作比以前的工作中主张的全球(世界)参考框架更准确,更强大。我们的代码可在https://github.com/boreshkinai/delta-interpolator上公开获取。
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Research on automated essay scoring has become increasing important because it serves as a method for evaluating students' written-responses at scale. Scalable methods for scoring written responses are needed as students migrate to online learning environments resulting in the need to evaluate large numbers of written-response assessments. The purpose of this study is to describe and evaluate three active learning methods than can be used to minimize the number of essays that must be scored by human raters while still providing the data needed to train a modern automated essay scoring system. The three active learning methods are the uncertainty-based, the topological-based, and the hybrid method. These three methods were used to select essays included as part of the Automated Student Assessment Prize competition that were then classified using a scoring model that was training with the bidirectional encoder representations from transformer language model. All three active learning methods produced strong results, with the topological-based method producing the most efficient classification. Growth rate accuracy was also evaluated. The active learning methods produced different levels of efficiency under different sample size allocations but, overall, all three methods were highly efficient and produced classifications that were similar to one another.
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Strategic test allocation plays a major role in the control of both emerging and existing pandemics (e.g., COVID-19, HIV). Widespread testing supports effective epidemic control by (1) reducing transmission via identifying cases, and (2) tracking outbreak dynamics to inform targeted interventions. However, infectious disease surveillance presents unique statistical challenges. For instance, the true outcome of interest - one's positive infectious status, is often a latent variable. In addition, presence of both network and temporal dependence reduces the data to a single observation. As testing entire populations regularly is neither efficient nor feasible, standard approaches to testing recommend simple rule-based testing strategies (e.g., symptom based, contact tracing), without taking into account individual risk. In this work, we study an adaptive sequential design involving n individuals over a period of {\tau} time-steps, which allows for unspecified dependence among individuals and across time. Our causal target parameter is the mean latent outcome we would have obtained after one time-step, if, starting at time t given the observed past, we had carried out a stochastic intervention that maximizes the outcome under a resource constraint. We propose an Online Super Learner for adaptive sequential surveillance that learns the optimal choice of tests strategies over time while adapting to the current state of the outbreak. Relying on a series of working models, the proposed method learns across samples, through time, or both: based on the underlying (unknown) structure in the data. We present an identification result for the latent outcome in terms of the observed data, and demonstrate the superior performance of the proposed strategy in a simulation modeling a residential university environment during the COVID-19 pandemic.
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Supervised machine learning-based medical image computing applications necessitate expert label curation, while unlabelled image data might be relatively abundant. Active learning methods aim to prioritise a subset of available image data for expert annotation, for label-efficient model training. We develop a controller neural network that measures priority of images in a sequence of batches, as in batch-mode active learning, for multi-class segmentation tasks. The controller is optimised by rewarding positive task-specific performance gain, within a Markov decision process (MDP) environment that also optimises the task predictor. In this work, the task predictor is a segmentation network. A meta-reinforcement learning algorithm is proposed with multiple MDPs, such that the pre-trained controller can be adapted to a new MDP that contains data from different institutes and/or requires segmentation of different organs or structures within the abdomen. We present experimental results using multiple CT datasets from more than one thousand patients, with segmentation tasks of nine different abdominal organs, to demonstrate the efficacy of the learnt prioritisation controller function and its cross-institute and cross-organ adaptability. We show that the proposed adaptable prioritisation metric yields converging segmentation accuracy for the novel class of kidney, unseen in training, using between approximately 40\% to 60\% of labels otherwise required with other heuristic or random prioritisation metrics. For clinical datasets of limited size, the proposed adaptable prioritisation offers a performance improvement of 22.6\% and 10.2\% in Dice score, for tasks of kidney and liver vessel segmentation, respectively, compared to random prioritisation and alternative active sampling strategies.
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To offer accurate and diverse recommendation services, recent methods use auxiliary information to foster the learning process of user and item representations. Many SOTA methods fuse different sources of information (user, item, knowledge graph, tags, etc.) into a graph and use Graph Neural Networks to introduce the auxiliary information through the message passing paradigm. In this work, we seek an alternative framework that is light and effective through self-supervised learning across different sources of information, particularly for the commonly accessible item tag information. We use a self-supervision signal to pair users with the auxiliary information associated with the items they have interacted with before. To achieve the pairing, we create a proxy training task. For a given item, the model predicts the correct pairing between the representations obtained from the users that have interacted with this item and the assigned tags. This design provides an efficient solution, using the auxiliary information directly to enhance the quality of user and item embeddings. User behavior in recommendation systems is driven by the complex interactions of many factors behind the decision-making processes. To make the pairing process more fine-grained and avoid embedding collapse, we propose an intent-aware self-supervised pairing process where we split the user embeddings into multiple sub-embedding vectors. Each sub-embedding vector captures a specific user intent via self-supervised alignment with a particular cluster of tags. We integrate our designed framework with various recommendation models, demonstrating its flexibility and compatibility. Through comparison with numerous SOTA methods on seven real-world datasets, we show that our method can achieve better performance while requiring less training time. This indicates the potential of applying our approach on web-scale datasets.
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Artificial Intelligence (AI) is one of the most transformative technologies of the 21st century. The extent and scope of future AI capabilities remain a key uncertainty, with widespread disagreement on timelines and potential impacts. As nations and technology companies race toward greater complexity and autonomy in AI systems, there are concerns over the extent of integration and oversight of opaque AI decision processes. This is especially true in the subfield of machine learning (ML), where systems learn to optimize objectives without human assistance. Objectives can be imperfectly specified or executed in an unexpected or potentially harmful way. This becomes more concerning as systems increase in power and autonomy, where an abrupt capability jump could result in unexpected shifts in power dynamics or even catastrophic failures. This study presents a hierarchical complex systems framework to model AI risk and provide a template for alternative futures analysis. Survey data were collected from domain experts in the public and private sectors to classify AI impact and likelihood. The results show increased uncertainty over the powerful AI agent scenario, confidence in multiagent environments, and increased concern over AI alignment failures and influence-seeking behavior.
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神经场通过将坐标输入映射到采样值来模型信号。从视觉,图形到生物学和天文学的许多领域,它们正成为越来越重要的主链体系结构。在本文中,我们探讨了这些网络中常见的调理机制之间的差异,这是将神经场从信号的记忆转移到概括的基本要素,其中共同建模了位于歧管上的一组信号。特别是,我们对这些机制的缩放行为感兴趣,以对日益高维的调理变量感兴趣。正如我们在实验中显示的那样,高维条件是建模复杂数据分布的关键,因此,确定哪种体系结构在处理此类问题时最能实现哪种选择。为此,我们运行了使用串联,超网络和基于注意力的调理策略对2D,3D和4D信号进行建模的实验,这是文献中尚未进行的必要但费力的努力。我们发现,基于注意力的条件在各种环境中的其他方法都优于其他方法。
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最近在无监督学习框架中为多元时间表制定代表性的努力。这种表示可以证明在活动识别,健康监测和异常检测等任务中有益。在本文中,我们考虑了一个设置,在该设置中,我们在动态图中观察到每个节点处的时间序列。我们提出了一个名为GraphTNC的框架,用于无监督的图表和时间序列的联合表示。我们的方法采用了对比度学习策略。基于一个假设,即时间序和图演进动力学是平滑的,我们确定了信号表现出近似平稳性的本地时间窗口。然后,我们训练一个编码,该编码允许在社区内分布非邻居信号的分布。我们首先使用合成数据证明了我们提出的框架的性能,随后我们证明它可以证明对使用现实世界数据集的分类任务有益。
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在医学图像分析中需要进行几次学习的能力是对支持图像数据的有效利用,该数据被标记为对新类进行分类或细分新类,该任务否则需要更多的培训图像和专家注释。这项工作描述了一种完全3D原型的几种分段算法,因此,训练有素的网络可以有效地适应培训中缺乏的临床有趣结构,仅使用来自不同研究所的几个标记图像。首先,为了弥补机构在新型类别的情节适应中的广泛认识的空间变异性,新型的空间注册机制被整合到原型学习中,由分割头和空间对齐模块组成。其次,为了帮助训练观察到的不完美比对,提出了支持掩模调节模块,以进一步利用支持图像中可用的注释。使用589个骨盆T2加权MR图像的数据集分割了八个对介入计划的解剖结构的应用,该实验是针对介入八个机构的八个解剖结构的应用。结果证明了3D公式中的每种,空间登记和支持掩模条件的功效,所有这些条件都独立或集体地做出了积极的贡献。与先前提出的2D替代方案相比,不管支持数据来自相同还是不同的机构,都具有统计学意义的少量分割性能。
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自动摘要评估对于机器生成和人为生产的摘要都有用。自动评估给定文档的摘要文本启用,例如,摘要生成系统开发和检测不适当的摘要。摘要评估可以以多种模式进行:排名摘要生成系统;对特定文档的排名摘要;并在绝对规模上估算文档 - 苏格尔对的质量。带有注释的现有数据集用于摘要评估,通常基于新闻摘要数据集,例如CNN/DailyMail或XSUM。在这项工作中,我们描述了一个新的数据集,即播客摘要评估语料库,这是由TREC2020的人类专家评估的播客摘要集。与现有的摘要评估数据相比,该数据集具有两个独特的方面:(i)基于语音播客的长输入,文档; (ii)有机会在播客语料库中检测不适当的参考摘要。首先,我们检查了现有的评估方法,包括无模型和基于模型的方法,并为此长输入摘要评估数据集提供基准结果。其次,为了过滤参考参考文献配对以进行培训,我们采用摘要评估进行数据选择。这两个方面的实验结果为摘要评估和发电任务提供了有趣的见解。播客摘要评估数据可用。
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