自二十年前引入以来,人们对时间序列的早期分类问题一直在越来越兴趣。这个问题概括了经典的时间序列分类,以询问我们是否可以在仅看到目标模式的某些前缀后,以足够的准确性和置信度分类。这个想法是,较早的分类将使我们能够立即采取行动,在某个实践干预措施的领域中。例如,该干预措施可能会发出警报或在汽车中施加制动器。在这项工作中,我们提出了令人惊讶的主张。尽管有数十种有关时间序列的早期分类的论文,但尚不清楚它们中的任何一个都可以在现实世界中工作。问题本身本身不是算法,而是含糊不清的问题描述。从本质上讲,所有算法都对问题做出了隐式和不必要的假设,即使他们的结果表明他们可以获得近乎完美的结果,也会确保它们会受到误报和假否定的困扰。我们将通过新颖的见解和实验来解释我们的发现,并向社区提供建议。
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时间序列的异常检测一直是数据科学中常年重要的主题,论文可以追溯到1950年代。但是,近年来,对这个主题引起了人们的兴趣,其中很大程度上是由于深度学习在其他领域和其他时间序列任务中的成功驱动。这些论文中的大多数对Yahoo,Numenta,NASA等创建的一个或多个流行的基准数据集进行了测试。在这项工作中,我们提出了令人惊讶的主张。这些数据集中的大多数示例都遭受四个缺陷中的一个或多个。由于这四个缺陷,我们认为许多发表的异常检测算法的比较可能是不可靠的,更重要的是,近年来,许多明显的进展可能都是幻觉。除了证明这些主张外,我们还介绍了UCR时间序列异常存档。我们认为,该资源将通过为社区提供基准,从而可以在方法和有意义的总体进步范围之间进行有意义的比较,从而扮演与UCR时间序列分类档案相似的角色。
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许多时间序列数据挖掘问题可以通过重复使用距离度量来解决。此类任务的示例包括相似性搜索,聚类,分类,异常检测和分割。在过去的二十年中,人们已经知道,在大多数域中,动态时间扭曲(DTW)距离度量是用于大多数任务的最佳措施。由于经典的DTW算法具有二次的时间复杂性,因此引入了许多想法,以减少其摊销时间或快速近似它。最引用的近似方法之一是FastDTW。 FastDTW算法已有超过一千个引用,并已在数百个研究工作中明确使用。在这项工作中,我们提出了令人惊讶的主张。在任何现实的数据挖掘应用程序中,近似FastDTW都比确切的DTW慢得多。这个事实显然对使用此算法的社区具有影响:允许其解决更大的数据集,获得确切的结果并在更少的时间内完成。
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近年来,传感器技术中有前所未有的技术进步,传感器变得比以往任何时候都更实惠。因此,传感器驱动数据收集越来越多地成为全球研究人员的吸引力和实用的选择。这些数据通常以时间序列数据的形式提取,这可以用数据挖掘技术来研究,以总结一系列受试者的行为,包括人类和动物。虽然启用廉价和质量收集数据,但连续传感器数据记录在大小和体积中大的数据集,这是在及时处理和分析传统技术的具有挑战性。这种收集的传感器数据通常以时间序列数据的形式提取。文献中有两种主要方法,即基于形状的分类和基于特征的分类。基于形状的分类根据距离测量确定最佳类。另一方面,基于功能的分类,根据时间序列定义的功能,找到时间序列的属性并找到最佳类。在本文中,我们证明这两种技术都不会使一些问题占主导地位,但两者都可能是最好的。换句话说,在一个问题上,可能的技术可以更好地对行为的一个子集更好,而另一技术对于另一个行为的子集更好。我们介绍了一种混合算法来分类行为,使用两个形状和特征措施,在从传感器收集的弱标记时间序列数据中,以量化由受试者执行的特定行为。我们展示了我们的算法可以基于形状和特征的组合,强大地分类真实,嘈杂和复杂的数据集,并在现实世界数据集中测试了我们所提出的算法。
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The most useful data mining primitives are distance measures. With an effective distance measure, it is possible to perform classification, clustering, anomaly detection, segmentation, etc. For single-event time series Euclidean Distance and Dynamic Time Warping distance are known to be extremely effective. However, for time series containing cyclical behaviors, the semantic meaningfulness of such comparisons is less clear. For example, on two separate days the telemetry from an athlete workout routine might be very similar. The second day may change the order in of performing push-ups and squats, adding repetitions of pull-ups, or completely omitting dumbbell curls. Any of these minor changes would defeat existing time series distance measures. Some bag-of-features methods have been proposed to address this problem, but we argue that in many cases, similarity is intimately tied to the shapes of subsequences within these longer time series. In such cases, summative features will lack discrimination ability. In this work we introduce PRCIS, which stands for Pattern Representation Comparison in Series. PRCIS is a distance measure for long time series, which exploits recent progress in our ability to summarize time series with dictionaries. We will demonstrate the utility of our ideas on diverse tasks and datasets.
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Incivility remains a major challenge for online discussion platforms, to such an extent that even conversations between well-intentioned users can often derail into uncivil behavior. Traditionally, platforms have relied on moderators to -- with or without algorithmic assistance -- take corrective actions such as removing comments or banning users. In this work we propose a complementary paradigm that directly empowers users by proactively enhancing their awareness about existing tension in the conversation they are engaging in and actively guides them as they are drafting their replies to avoid further escalation. As a proof of concept for this paradigm, we design an algorithmic tool that provides such proactive information directly to users, and conduct a user study in a popular discussion platform. Through a mixed methods approach combining surveys with a randomized controlled experiment, we uncover qualitative and quantitative insights regarding how the participants utilize and react to this information. Most participants report finding this proactive paradigm valuable, noting that it helps them to identify tension that they may have otherwise missed and prompts them to further reflect on their own replies and to revise them. These effects are corroborated by a comparison of how the participants draft their reply when our tool warns them that their conversation is at risk of derailing into uncivil behavior versus in a control condition where the tool is disabled. These preliminary findings highlight the potential of this user-centered paradigm and point to concrete directions for future implementations.
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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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Recent work pre-training Transformers with self-supervised objectives on large text corpora has shown great success when fine-tuned on downstream NLP tasks including text summarization. However, pre-training objectives tailored for abstractive text summarization have not been explored. Furthermore there is a lack of systematic evaluation across diverse domains. In this work, we propose pre-training large Transformer-based encoder-decoder models on massive text corpora with a new selfsupervised objective. In PEGASUS, important sentences are removed/masked from an input document and are generated together as one output sequence from the remaining sentences, similar to an extractive summary. We evaluated our best PEGASUS model on 12 downstream summarization tasks spanning news, science, stories, instructions, emails, patents, and legislative bills. Experiments demonstrate it achieves state-of-the-art performance on all 12 downstream datasets measured by ROUGE scores. Our model also shows surprising performance on low-resource summarization, surpassing previous state-of-the-art results on 6 datasets with only 1000 examples. Finally we validated our results using human evaluation and show that our model summaries achieve human performance on multiple datasets.
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现在通常用于高风险设置,如医疗诊断,如医疗诊断,那么需要不确定量化,以避免后续模型失败。无分发的不确定性量化(无分布UQ)是用户友好的范式,用于为这种预测创建统计上严格的置信区间/集合。批判性地,间隔/集合有效而不进行分布假设或模型假设,即使具有最多许多DataPoints也具有显式保证。此外,它们适应输入的难度;当输入示例很困难时,不确定性间隔/集很大,信号传达模型可能是错误的。在没有多大的工作和没有再培训的情况下,可以在任何潜在的算法(例如神经网络)上使用无分​​发方法,以产生置信度集,以便包含用户指定概率,例如90%。实际上,这些方法易于理解和一般,应用于计算机视觉,自然语言处理,深度加强学习等领域出现的许多现代预测问题。这种实践介绍是针对对无需统计学家的免费UQ的实际实施感兴趣的读者。我们通过实际的理论和无分发UQ的应用领导读者,从保形预测开始,并使无关的任何风险的分布控制,如虚假发现率,假阳性分布检测,等等。我们将包括Python中的许多解释性插图,示例和代码样本,具有Pytorch语法。目标是提供读者对无分配UQ的工作理解,使它们能够将置信间隔放在算法上,其中包含一个自包含的文档。
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Advocates of algorithmic techniques like data mining argue that these techniques eliminate human biases from the decision-making process. But an algorithm is only as good as the data it works with. Data is frequently imperfect in ways that allow these algorithms to inherit the prejudices of prior decision makers. In other cases, data may simply reflect the widespread biases that persist in society at large. In still others, data mining can discover surprisingly useful regularities that are really just preexisting patterns of exclusion and inequality. Unthinking reliance on data mining can deny historically disadvantaged and vulnerable groups full participation in society. Worse still, because the resulting discrimination is almost always an unintentional emergent property of the algorithm's use rather than a conscious choice by its programmers, it can be unusually hard to identify the source of the problem or to explain it to a court. This Essay examines these concerns through the lens of American antidiscrimination law-more particularly, through Title
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We propose the Detailed Outline Control (DOC) framework for improving long-range plot coherence when automatically generating several-thousand-word-long stories. DOC consists of two complementary components: a detailed outliner and a detailed controller. The detailed outliner creates a more detailed, hierarchically structured outline, shifting creative burden from the main drafting procedure to the planning stage. The detailed controller ensures the more detailed outline is still respected during generation by controlling story passages to align with outline details. In human evaluations of automatically generated stories, DOC substantially outperforms a strong Re3 baseline (Yang et al., 2022) on plot coherence (22.5% absolute gain), outline relevance (28.2%), and interestingness (20.7%). Humans also judged DOC to be much more controllable in an interactive generation setting.
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当前的语言模型可以产生高质量的文本。他们只是复制他们之前看到的文本,或者他们学习了普遍的语言抽象吗?要取笑这些可能性,我们介绍了乌鸦,这是一套评估生成文本的新颖性,专注于顺序结构(n-gram)和句法结构。我们将这些分析应用于四种神经语言模型(LSTM,变压器,变换器-XL和GPT-2)。对于本地结构 - 例如,单个依赖性 - 模型生成的文本比来自每个模型的测试集的人类生成文本的基线显着不那么新颖。对于大规模结构 - 例如,总句结构 - 模型生成的文本与人生成的基线一样新颖甚至更新颖,但模型仍然有时复制,在某些情况下,在训练集中重复超过1000字超过1,000字的通道。我们还表现了广泛的手动分析,表明GPT-2的新文本通常在形态学和语法中形成良好,但具有合理的语义问题(例如,是自相矛盾)。
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基于签名的技术使数学洞察力洞悉不断发展的数据的复杂流之间的相互作用。这些见解可以自然地转化为理解流数据的数值方法,也许是由于它们的数学精度,已被证明在数据不规则而不是固定的情况下分析流的数据以及数据和数据的尺寸很有用样本量均为中等。了解流的多模式数据是指数的:$ d $ d $的字母中的$ n $字母中的一个单词可以是$ d^n $消息之一。签名消除了通过采样不规则性引起的指数级噪声,但仍然存在指数量的信息。这项调查旨在留在可以直接管理指数缩放的域中。在许多问题中,可伸缩性问题是一个重要的挑战,但需要另一篇调查文章和进一步的想法。这项调查描述了一系列环境集足够小以消除大规模机器学习的可能性,并且可以有效地使用一小部分免费上下文和原则性功能。工具的数学性质可以使他们对非数学家的使用恐吓。本文中介绍的示例旨在弥合此通信差距,并提供从机器学习环境中绘制的可进行的工作示例。笔记本可以在线提供这些示例中的一些。这项调查是基于伊利亚·雪佛兰(Ilya Chevryev)和安德烈·科米利津(Andrey Kormilitzin)的早期论文,它们在这种机械开发的较早时刻大致相似。本文说明了签名提供的理论见解是如何在对应用程序数据的分析中简单地实现的,这种方式在很大程度上对数据类型不可知。
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长序列中的子序列异常检测是在广泛域中应用的重要问题。但是,迄今为止文献中提出的方法具有严重的局限性:它们要么需要用于设计异常发现算法的先前领域知识,要么在与相同类型的复发异常情况下使用繁琐且昂贵。在这项工作中,我们解决了这些问题,并提出了一种适用于域的不可知论次序列异常检测的方法。我们的方法series2graph基于新型低维嵌入子序列的图表。 Series2Graph不需要标记的实例(例如监督技术)也不需要无异常的数据(例如零阳性学习技术),也不需要识别长度不同的异常。在迄今为止使用的最大合成和真实数据集的实验结果表明,所提出的方法正确地识别了单一和复发异常,而无需任何先验的特征,以优于多种差距的准确性,同时提高了几种竞争的方法,同时又表现出色更快的数量级。本文出现在VLDB 2020中。
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部署的AI系统通常不起作用。它们可以随意地构造,不加选择地部署并欺骗性地促进。然而,尽管有这一现实,但学者,新闻界和决策者对功能的关注很少。这导致技术和政策解决方案的重点是“道德”或价值一致的部署,通常会跳过先前的问题,即给定系统功能或完全提供任何好处。描述各种功能失败的危害,我们分析一组案例研究,以创建已知的AI功能问题的分类法。然后,我们指出的是政策和组织响应,这些策略和组织响应经常被忽略,并在功能成为重点后变得更容易获得。我们认为功能是一项有意义的AI政策挑战,是保护受影响社区免受算法伤害的必要第一步。
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我们介绍了Sparrow,这是一个寻求信息的对话代理,与提示的语言模型基线相比,训练有素,更有帮助,正确和无害。我们使用从人类反馈中的强化学习来培训我们的模型,以帮助人类评估者判断代理人的行为。首先,为了使我们的代理人更有帮助和无害,我们将良好对话的要求分解为代理人应遵循的自然语言规则,并分别向评估者询问每个规则。我们证明,这种崩溃使我们能够收集对代理行为的更多针对性的人类判断,并允许更有效的规则条件奖励模型。其次,我们的代理商在收集对模型声明的偏好判决时提供了支持事实主张的来源的证据。对于事实问题,麻雀提供的证据支持了78%的时间。比基线比基线更享受麻雀,同时对人类的对抗性探测更具弹性,在探测时只有8%的时间违反了我们的规则。最后,我们进行了广泛的分析,表明尽管我们的模型学会遵守我们的规则,但它可以表现出分布偏见。
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讨论了与科学,工程,建筑和人为因素相关的月球表面上的运输设施问题。未来十年制造的后勤决策可能对财务成功至关重要。除了概述一些问题及其与数学和计算的关系外,本文还为决策者,科学家和工程师提供了有用的资源。
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The literature on machine learning in the context of data streams is vast and growing. However, many of the defining assumptions regarding data-stream learning tasks are too strong to hold in practice, or are even contradictory such that they cannot be met in the contexts of supervised learning. Algorithms are chosen and designed based on criteria which are often not clearly stated, for problem settings not clearly defined, tested in unrealistic settings, and/or in isolation from related approaches in the wider literature. This puts into question the potential for real-world impact of many approaches conceived in such contexts, and risks propagating a misguided research focus. We propose to tackle these issues by reformulating the fundamental definitions and settings of supervised data-stream learning with regard to contemporary considerations of concept drift and temporal dependence; and we take a fresh look at what constitutes a supervised data-stream learning task, and a reconsideration of algorithms that may be applied to tackle such tasks. Through and in reflection of this formulation and overview, helped by an informal survey of industrial players dealing with real-world data streams, we provide recommendations. Our main emphasis is that learning from data streams does not impose a single-pass or online-learning approach, or any particular learning regime; and any constraints on memory and time are not specific to streaming. Meanwhile, there exist established techniques for dealing with temporal dependence and concept drift, in other areas of the literature. For the data streams community, we thus encourage a shift in research focus, from dealing with often-artificial constraints and assumptions on the learning mode, to issues such as robustness, privacy, and interpretability which are increasingly relevant to learning in data streams in academic and industrial settings.
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保证案件旨在为其最高主张的真理提供合理的信心,这通常涉及安全或保障。那么一个自然的问题是,案件提供了“多少”信心?我们认为,置信度不能简化为单个属性或测量。取而代之的是,我们建议它应该基于以三种不同观点的属性为基础:正面,消极和残留疑问。积极的观点考虑了该案件的证据和总体论点结合起来的程度,以表明其主张的信念是正当的。我们为理由设置了一个高标准,要求它是不可行的。对此的主要积极度量是健全性,它将论点解释为逻辑证明。对证据的信心可以概率地表达,我们使用确认措施来确保证据的“权重”跨越了一定的阈值。此外,可以通过使用概率逻辑的参数步骤从证据中汇总概率,以产生我们所谓的索赔概率估值。负面观点记录了对案件的怀疑和挑战,通常表示为叛逆者及其探索和解决。保证开发商必须防止确认偏见,并应在制定案件时大力探索潜在的叛逆者,并应记录下来及其解决方案,以避免返工并帮助审阅者。残留疑问:世界不确定,因此并非所有潜在的叛逆者都可以解决。我们探索风险,可能认为它们是可以接受或不可避免的。但是,至关重要的是,这些判断是有意识的判断,并且在保证案例中记录下来。本报告详细介绍了这些观点,并指示了我们的保证2.0的原型工具集如何协助他们的评估。
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State-of-the-art computer vision systems are trained to predict a fixed set of predetermined object categories. This restricted form of supervision limits their generality and usability since additional labeled data is needed to specify any other visual concept. Learning directly from raw text about images is a promising alternative which leverages a much broader source of supervision. We demonstrate that the simple pre-training task of predicting which caption goes with which image is an efficient and scalable way to learn SOTA image representations from scratch on a dataset of 400 million (image, text) pairs collected from the internet. After pre-training, natural language is used to reference learned visual concepts (or describe new ones) enabling zero-shot transfer of the model to downstream tasks. We study the performance of this approach by benchmarking on over 30 different existing computer vision datasets, spanning tasks such as OCR, action recognition in videos, geo-localization, and many types of fine-grained object classification. The model transfers non-trivially to most tasks and is often competitive with a fully supervised baseline without the need for any dataset specific training. For instance, we match the accuracy of the original ResNet-50 on ImageNet zero-shot without needing to use any of the 1.28 million training examples it was trained on. We release our code and pre-trained model weights at https://github.com/OpenAI/CLIP.
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