基于稳定性的概念,我们研究嘈杂随机迷你批量迭代算法的泛化界限。近年来,基于稳定性(Mou等,2018; Li等,2020)和信息理论方法(Mou等,2018)和信息理论方法(徐和Raginsky,2017; Negrea等,2019年; Steinke和Zakynthinou,2020; Haghifam等,2020)。在本文中,我们统一和基本上概括了基于稳定的泛化范围,并进行了三个技术进步。首先,我们在预期(不统一)稳定性方面绑定了一般噪声随机迭代算法(不一定梯度下降)的泛化误差。预期的稳定性又可以通过LE凸轮风格的偏差界定。与o(1 / \ sqrt {n})的许多现有范围不同,这种界限具有O(1 / n)样本依赖性。其次,我们介绍指数族族朗文动力学(EFLD),这是SGLD的大量概括,其允许与随机梯度下降(SGD)一起使用的指数家庭噪声。我们为一般EFLD算法建立基于数据相关的预期稳定性的泛化界。第三,我们考虑一个重要的特殊情况:EFLD的一个重要特殊情况:嘈杂的符号-SGD,它使用{-1,+ 1}的Bernoulli噪声扩展标志SGD。 EFLD的危识符号的泛化界限暗示了EFLD的暗示,我们还建立了算法的优化保证。此外,我们在基准数据集中呈现实证结果,以说明我们的界限与现有界限不上且定量。
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远程感知的地理空间数据对于包括精确农业,城市规划,灾害监测和反应以及气候变化研究等应用至关重要。对于在类似的计算机视觉任务中的深度神经网络的成功和可用的远程感测图像的纯粹体积的情况下,深入学习方法尤为前接受了许多遥感任务。然而,数据收集方法的方差和地理空间元数据的处理使得深度学习方法的应用成为远程感测的数据不动性。例如,卫星图像通常包括超出红色,绿色和蓝色的额外光谱频带,并且必须连接到可以具有不同坐标系,界限和分辨率的其他地理空间数据源。为了帮助实现遥感应用的深度学习的潜力,我们介绍了一个Pythono库的Torchgeo,用于将地理空间数据集成到Pytorch深度学习生态系统中。 Torchgeo为各种基准数据集,用于通用地理空间数据源的可组合数据集,用于地理空间数据的采样器以及使用多光谱图像的转换的数据加载器。 Torchgeo也是第一个为多光谱卫星图像提供预先训练的模型的库(例如,使用Sentinel 2卫星的所有频段的模型),允许在下游遥感任务上传输学习,其中包含有限的标记数据。我们使用Torchgeo在现有数据集上创建可重复的基准结果,并将我们的建议方法用于直通预处理地理空间图像。 Torchgeo是开源的,可在GitHub上提供:https://github.com/microsoft/torchgeo。
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已经研究了几十年的上下文多武装匪,并适应了各种应用,如在线广告和个性化推荐。为了解决匪徒的开发探索权衡,有三种主要技术:epsilon - 贪婪,汤普森采样(TS)和上置信度(UCB)。在最近的文献中,线性上下窗匪徒采用了脊回归来估计奖励功能,并将其与TS或UCB策略结合起来的探索。但是,这行作品明确假设奖励基于ARM向量的线性函数,在现实世界数据集中可能不是真的。为了克服这一挑战,已经提出了一系列神经基的强盗算法,其中分配了神经网络以学习基础奖励功能,并且TS或UCB适于探索。在本文中,我们提出了一种具有新的探索策略的神经基匪徒方法。除了利用神经网络(开发网络)外学习奖励功能之外,与目前估计的奖励相比,EE-Net采用另一个神经网络(勘探网络)来自适应地学习潜在的增益。然后,构建决策者以将输出与剥削和探索网络组合起来。我们证明了EE-Net实现了$ \ mathcal {o}(\ sqrt {t \ log t})$后悔,它比现有最先进的神经强盗算法更紧密($ \ mathcal {o}(\基于UCB和TS的SQRT {T} \ log t)$。通过对四世界数据集的广泛实验,我们表明EE-Net优于现有的线性和神经匪徒的方法。
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When testing conditions differ from those represented in training data, so-called out-of-distribution (OOD) inputs can mar the reliability of black-box learned components in the modern robot autonomy stack. Therefore, coping with OOD data is an important challenge on the path towards trustworthy learning-enabled open-world autonomy. In this paper, we aim to demystify the topic of OOD data and its associated challenges in the context of data-driven robotic systems, drawing connections to emerging paradigms in the ML community that study the effect of OOD data on learned models in isolation. We argue that as roboticists, we should reason about the overall system-level competence of a robot as it performs tasks in OOD conditions. We highlight key research questions around this system-level view of OOD problems to guide future research toward safe and reliable learning-enabled autonomy.
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Migraine is a high-prevalence and disabling neurological disorder. However, information migraine management in real-world settings could be limited to traditional health information sources. In this paper, we (i) verify that there is substantial migraine-related chatter available on social media (Twitter and Reddit), self-reported by migraine sufferers; (ii) develop a platform-independent text classification system for automatically detecting self-reported migraine-related posts, and (iii) conduct analyses of the self-reported posts to assess the utility of social media for studying this problem. We manually annotated 5750 Twitter posts and 302 Reddit posts. Our system achieved an F1 score of 0.90 on Twitter and 0.93 on Reddit. Analysis of information posted by our 'migraine cohort' revealed the presence of a plethora of relevant information about migraine therapies and patient sentiments associated with them. Our study forms the foundation for conducting an in-depth analysis of migraine-related information using social media data.
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Data compression is becoming critical for storing scientific data because many scientific applications need to store large amounts of data and post process this data for scientific discovery. Unlike image and video compression algorithms that limit errors to primary data, scientists require compression techniques that accurately preserve derived quantities of interest (QoIs). This paper presents a physics-informed compression technique implemented as an end-to-end, scalable, GPU-based pipeline for data compression that addresses this requirement. Our hybrid compression technique combines machine learning techniques and standard compression methods. Specifically, we combine an autoencoder, an error-bounded lossy compressor to provide guarantees on raw data error, and a constraint satisfaction post-processing step to preserve the QoIs within a minimal error (generally less than floating point error). The effectiveness of the data compression pipeline is demonstrated by compressing nuclear fusion simulation data generated by a large-scale fusion code, XGC, which produces hundreds of terabytes of data in a single day. Our approach works within the ADIOS framework and results in compression by a factor of more than 150 while requiring only a few percent of the computational resources necessary for generating the data, making the overall approach highly effective for practical scenarios.
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'Actions' play a vital role in how humans interact with the world. Thus, autonomous agents that would assist us in everyday tasks also require the capability to perform 'Reasoning about Actions & Change' (RAC). This has been an important research direction in Artificial Intelligence (AI) in general, but the study of RAC with visual and linguistic inputs is relatively recent. The CLEVR_HYP (Sampat et. al., 2021) is one such testbed for hypothetical vision-language reasoning with actions as the key focus. In this work, we propose a novel learning strategy that can improve reasoning about the effects of actions. We implement an encoder-decoder architecture to learn the representation of actions as vectors. We combine the aforementioned encoder-decoder architecture with existing modality parsers and a scene graph question answering model to evaluate our proposed system on the CLEVR_HYP dataset. We conduct thorough experiments to demonstrate the effectiveness of our proposed approach and discuss its advantages over previous baselines in terms of performance, data efficiency, and generalization capability.
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'Actions' play a vital role in how humans interact with the world. Thus, autonomous agents that would assist us in everyday tasks also require the capability to perform 'Reasoning about Actions & Change' (RAC). Recently, there has been growing interest in the study of RAC with visual and linguistic inputs. Graphs are often used to represent semantic structure of the visual content (i.e. objects, their attributes and relationships among objects), commonly referred to as scene-graphs. In this work, we propose a novel method that leverages scene-graph representation of images to reason about the effects of actions described in natural language. We experiment with existing CLEVR_HYP (Sampat et. al, 2021) dataset and show that our proposed approach is effective in terms of performance, data efficiency, and generalization capability compared to existing models.
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This paper aims to provide an unsupervised modelling approach that allows for a more flexible representation of text embeddings. It jointly encodes the words and the paragraphs as individual matrices of arbitrary column dimension with unit Frobenius norm. The representation is also linguistically motivated with the introduction of a novel similarity metric. The proposed modelling and the novel similarity metric exploits the matrix structure of embeddings. We then go on to show that the same matrices can be reshaped into vectors of unit norm and transform our problem into an optimization problem over the spherical manifold. We exploit manifold optimization to efficiently train the matrix embeddings. We also quantitatively verify the quality of our text embeddings by showing that they demonstrate improved results in document classification, document clustering, and semantic textual similarity benchmark tests.
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Generalizability of time series forecasting models depends on the quality of model selection. Temporal cross validation (TCV) is a standard technique to perform model selection in forecasting tasks. TCV sequentially partitions the training time series into train and validation windows, and performs hyperparameter optmization (HPO) of the forecast model to select the model with the best validation performance. Model selection with TCV often leads to poor test performance when the test data distribution differs from that of the validation data. We propose a novel model selection method, H-Pro that exploits the data hierarchy often associated with a time series dataset. Generally, the aggregated data at the higher levels of the hierarchy show better predictability and more consistency compared to the bottom-level data which is more sparse and (sometimes) intermittent. H-Pro performs the HPO of the lowest-level student model based on the test proxy forecasts obtained from a set of teacher models at higher levels in the hierarchy. The consistency of the teachers' proxy forecasts help select better student models at the lowest-level. We perform extensive empirical studies on multiple datasets to validate the efficacy of the proposed method. H-Pro along with off-the-shelf forecasting models outperform existing state-of-the-art forecasting methods including the winning models of the M5 point-forecasting competition.
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