Domain adaptation aims to transfer the knowledge acquired by models trained on (data-rich) source domains to (low-resource) target domains, for which a popular method is invariant representation learning. While they have been studied extensively for classification and regression problems, how they apply to ranking problems, where the data and metrics have a list structure, is not well understood. Theoretically, we establish a domain adaptation generalization bound for ranking under listwise metrics such as MRR and NDCG. The bound suggests an adaptation method via learning list-level domain-invariant feature representations, whose benefits are empirically demonstrated by unsupervised domain adaptation experiments on real-world ranking tasks, including passage reranking. A key message is that for domain adaptation, the representations should be analyzed at the same level at which the metric is computed, as we show that learning invariant representations at the list level is most effective for adaptation on ranking problems.
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检索演示的生成模型比独立语言模型提供了许多好处:除了对给定查询的文字答案外,它们还提供了从可更新知识库中检索到的出处项目。但是,它们也是更复杂的系统,需要处理长输入。在这项工作中,我们介绍了FID Light,以强烈提高最先进的检索功能模型的效率,同时保持相同的有效性。我们的FID光模型将信息流从编码器(分别编码段落)限制为解码器(使用串联编码表示)。此外,我们通过文本源指针通过重新排列的功能调整FID光,以提高排名最高的出处精度。我们对七个知识密集任务(KILT)的各种实验表明,FID光线始终改善了查询潜伏期和有效性之间的帕累托前沿。带有源指向的FID光设置为六个苏格兰短裙任务的新最新结果,用于合并文本生成和出处检索评估,同时保持合理的效率。
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本文研究了针对知识密集型任务的检索型生成模型的多任务培训。我们建议通过利用知识密集型一代的独特属性来清理设定的训练:查询 - 答案对与知识库中的项目的联系。我们通过对相关性标签的信心阈值过滤训练示例,无论一对是通过知识库而回答的。我们在苏格兰语基准的七个组合任务上训练一个单一的数字化(FID)发电机。实验结果表明,我们的简单而有效的方法基本上改善了两个强烈不平衡任务的基线。并显示其余任务的改进较小或没有重大回归。此外,我们通过相关性标签采样量表很好地展示了我们的多任务培训,并且具有增加的模型容量,并实现了最先进的训练,并在七个苏格兰短裙任务中五个。
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最近,几种密集的检索(DR)模型已经证明了在搜索系统中无处不在的基于术语的检索的竞争性能。与基于术语的匹配相反,DR将查询和文档投影到密集的矢量空间中,并通过(大约)最近的邻居搜索检索结果。部署新系统(例如DR)不可避免地涉及其性能方面的权衡。通常,建立的检索系统按照效率和成本(例如查询延迟,索引吞吐量或存储要求)对其进行了良好的理解。在这项工作中,我们提出了一个具有一组标准的框架,这些框架超出了简单的有效性措施,可以彻底比较两个检索系统,并明确目标是评估一个系统的准备就绪,以取代另一个系统。这包括有效性和各种成本因素之间的仔细权衡考虑。此外,我们描述了护栏标准,因为即使是平均而言更好的系统,也可能会对少数查询产生系统性故障。护栏检查某些查询特性和新型故障类型的故障,这些故障仅在密集检索系统中才有可能。我们在网络排名方案上演示了我们的决策框架。在这种情况下,最先进的DR模型的结果令人惊讶,不仅是平均表现,而且通过一系列广泛的护栏测试,表现出不同的查询特性,词汇匹配,概括和回归次数的稳健性。无法预测将来博士是否会变得无处不在,但是这是一种可能的方法是通过重复应用决策过程(例如此处介绍的过程)。
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At the foundation of scientific evaluation is the labor-intensive process of peer review. This critical task requires participants to consume vast amounts of highly technical text. Prior work has annotated different aspects of review argumentation, but discourse relations between reviews and rebuttals have yet to be examined. We present DISAPERE, a labeled dataset of 20k sentences contained in 506 review-rebuttal pairs in English, annotated by experts. DISAPERE synthesizes label sets from prior work and extends them to include fine-grained annotation of the rebuttal sentences, characterizing their context in the review and the authors' stance towards review arguments. Further, we annotate every review and rebuttal sentence. We show that discourse cues from rebuttals can shed light on the quality and interpretation of reviews. Further, an understanding of the argumentative strategies employed by the reviewers and authors provides useful signal for area chairs and other decision makers.
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例如,查询是一个众所周知的信息检索任务,其中由用户选择文档作为搜索查询,目标是从大集合中检索相关文档。但是,文档通常涵盖主题的多个方面。要解决此方案,我们将通过示例介绍面位查询的任务,其中用户还可以指定除输入查询文档之外的更精细的粗体方面。我们专注于在科学文献搜索中的应用。我们设想能够沿着专门选择的修辞结构元素作为对此问题的一种解决方案来检索类似于查询科学纸的科学论文。在这项工作中,我们称之为方面的修辞结构元素,表明了科学论文的目标,方法或结果。我们介绍并描述了一个专家注释的测试集合,以评估培训的型号以执行此任务。我们的测试收集包括一个不同的50套英文查询文件,从计算语言学和机器学习场所绘制。我们仔细遵循TREC用于深度-K池(k = 100或250)使用的注释指南,结果数据收集包括具有高注释协议的分级相关性分数。在我们的数据集中评估的最先进模型显示出进一步的工作中的显着差距。可以在此处访问我们的数据集:https://github.com/iesl/csfcube
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In large-scale machine learning, recent works have studied the effects of compressing gradients in stochastic optimization in order to alleviate the communication bottleneck. These works have collectively revealed that stochastic gradient descent (SGD) is robust to structured perturbations such as quantization, sparsification, and delays. Perhaps surprisingly, despite the surge of interest in large-scale, multi-agent reinforcement learning, almost nothing is known about the analogous question: Are common reinforcement learning (RL) algorithms also robust to similar perturbations? In this paper, we investigate this question by studying a variant of the classical temporal difference (TD) learning algorithm with a perturbed update direction, where a general compression operator is used to model the perturbation. Our main technical contribution is to show that compressed TD algorithms, coupled with an error-feedback mechanism used widely in optimization, exhibit the same non-asymptotic theoretical guarantees as their SGD counterparts. We then extend our results significantly to nonlinear stochastic approximation algorithms and multi-agent settings. In particular, we prove that for multi-agent TD learning, one can achieve linear convergence speedups in the number of agents while communicating just $\tilde{O}(1)$ bits per agent at each time step. Our work is the first to provide finite-time results in RL that account for general compression operators and error-feedback in tandem with linear function approximation and Markovian sampling. Our analysis hinges on studying the drift of a novel Lyapunov function that captures the dynamics of a memory variable introduced by error feedback.
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With Twitter's growth and popularity, a huge number of views are shared by users on various topics, making this platform a valuable information source on various political, social, and economic issues. This paper investigates English tweets on the Russia-Ukraine war to analyze trends reflecting users' opinions and sentiments regarding the conflict. The tweets' positive and negative sentiments are analyzed using a BERT-based model, and the time series associated with the frequency of positive and negative tweets for various countries is calculated. Then, we propose a method based on the neighborhood average for modeling and clustering the time series of countries. The clustering results provide valuable insight into public opinion regarding this conflict. Among other things, we can mention the similar thoughts of users from the United States, Canada, the United Kingdom, and most Western European countries versus the shared views of Eastern European, Scandinavian, Asian, and South American nations toward the conflict.
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Solving portfolio management problems using deep reinforcement learning has been getting much attention in finance for a few years. We have proposed a new method using experts signals and historical price data to feed into our reinforcement learning framework. Although experts signals have been used in previous works in the field of finance, as far as we know, it is the first time this method, in tandem with deep RL, is used to solve the financial portfolio management problem. Our proposed framework consists of a convolutional network for aggregating signals, another convolutional network for historical price data, and a vanilla network. We used the Proximal Policy Optimization algorithm as the agent to process the reward and take action in the environment. The results suggested that, on average, our framework could gain 90 percent of the profit earned by the best expert.
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Autoencoders are a popular model in many branches of machine learning and lossy data compression. However, their fundamental limits, the performance of gradient methods and the features learnt during optimization remain poorly understood, even in the two-layer setting. In fact, earlier work has considered either linear autoencoders or specific training regimes (leading to vanishing or diverging compression rates). Our paper addresses this gap by focusing on non-linear two-layer autoencoders trained in the challenging proportional regime in which the input dimension scales linearly with the size of the representation. Our results characterize the minimizers of the population risk, and show that such minimizers are achieved by gradient methods; their structure is also unveiled, thus leading to a concise description of the features obtained via training. For the special case of a sign activation function, our analysis establishes the fundamental limits for the lossy compression of Gaussian sources via (shallow) autoencoders. Finally, while the results are proved for Gaussian data, numerical simulations on standard datasets display the universality of the theoretical predictions.
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