在随机上下文的强盗设置中,对遗憾最小化算法进行了广泛的研究,但是他们的实例最少的最佳武器识别对应物仍然很少研究。在这项工作中,我们将重点关注$(\ epsilon,\ delta)$ - $ \ textit {pac} $设置:给定策略类$ \ pi $,学习者的目标是返回策略的目标, $ \ pi \ in \ pi $的预期奖励在最佳政策的$ \ epsilon $之内,概率大于$ 1- \ delta $。我们表征了第一个$ \ textit {实例依赖性} $ PAC样品通过数量$ \ rho _ {\ pi} $的上下文匪徒的复杂性,并根据$ \ rho _ {\ pi} $提供匹配的上和下限不可知论和线性上下文最佳武器标识设置。我们表明,对于遗憾的最小化和实例依赖性PAC而言,无法同时最小化算法。我们的主要结果是一种新的实例 - 最佳和计算有效算法,该算法依赖于多项式呼叫对Argmax Oracle的调用。
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积极的学习方法在减少学习所需的样本数量方面表现出了巨大的希望。随着自动化学习系统被采用到实时的现实世界决策管道中,越来越重要的是,这种算法的设计考虑到了安全性。在这项工作中,我们研究了在互动环境中学习最佳安全决定的复杂性。我们将这个问题减少到约束的线性匪徒问题,我们的目标是找到满足某些(未知)安全限制的最佳手臂。我们提出了一种基于自适应的实验性设计算法,在显示ARM的难度与次优的难度之间,我们表现出了有效的交易。据我们所知,我们的结果是具有安全限制的线性匪徒最佳武器识别。实际上,我们证明了这种方法在合成和现实世界数据集上的表现很好。
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级别设置估计问题旨在查找域$ {\ cal x} $的所有点,其中一个未知函数$ f:{\ cal x} \ lightarrow \ mathbb {r} $超过阈值$ \ alpha $ 。估计基于可以在$ {\ cal x} $中顺序和自适应地选择的位置获取的嘈杂函数评估。阈值$ \ alpha $可以是\弹性{显式},并提供先验,或\ \ ich {隐式},相对于最佳函数值定义,即$ \ alpha =(1- \ epsilon)f(x_ \ AST)$关于给定$ \ epsilon> 0 $ why $ f(x_ \ ist)$是最大函数值,并且未知。在这项工作中,我们通过将其与最近的自适应实验设计方法相关联,为近期自适应实验设计方法提供了一种新的再现内核盗窃空间(RKHS)设置。我们假设可以通过RKHS中的函数近似于未知的拼写,并为此设置中隐含和显式案件提供新的算法,具有很强的理论保证。此外,在线性(内核)设置中,我们表明我们的界限几乎是最佳的,即,我们的上限与阈值线性匪徒的现有下限匹配。据我们所知,这项工作提供了第一个实例依赖性非渐近的上限,就匹配信息理论下限的水平设定估计的样本复杂性。
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这项工作考虑了最佳手臂识别的选择性采样问题。给定一组潜在选项$ \ mathcal {z} \ subset \ mathbb {r} ^ d $,学习者旨在计算概率大于1- \ delta $,$ \ arg \ max_ {z \ mathcal { z}} z ^ {\ top} \ theta _ {\ ast} $ where $ \ theta _ {\ art} $未知。在每个时间步骤中,潜在的测量$ x_t \ in \ mathcal {x} \ subset \ mathbb {r} ^ d $被绘制的iid,学习者可以选择采取测量,在这种情况下,他们观察到嘈杂的测量$ x ^ {\ top} \ theta _ {\ ast} $,或弃权采取测量并等待可能更多的信息点到达流。因此,学习者在他们采取的标签样本数量之间面临的基本折衷,并且当他们收集足够的证据来宣布最好的手臂并停止抽样时。这项工作的主要结果精确地表征了标记的样本和停止时间之间的这种权衡,并提供了一种算法,几乎最佳地实现了给出所需停止时间的最小标签复杂性。此外,我们表明最佳决策规则具有基于决定点是否处于椭圆形的简单几何形式。最后,我们的框架足以捕获先前作品的二进制分类。
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这项工作提出了一种为特定的自适应数据收集任务设计算法,如活动学习和纯探索多武装匪徒。与传统自适应算法的设计不同,依靠测量浓度和仔细分析来证明程序的正确性和样本复杂性,通过对来自信息理论下限的等效类别的等效类别的对抗训练来学习我们的自适应算法。特别地,学习了单个自适应学习算法,以为每个等价类的最佳自适应算法竞争。我们的程序只需输入可用查询,假设,丢失函数集和全查询预算集。这与现有的元学习工作相反,用于了解相对于显式,用户定义的子集或先前分布的自适应算法,这些工作是可能具有具有挑战性的问题,以便定义和不匹配到测试时间遇到的实例。当总查询预算非常小时,这项工作特别专注于制度,例如几十个,这远小于理论上衍生算法通常考虑的预算。我们执行合成实验,以证明培训程序的稳定性和有效性,然后评估来自实际数据的任务方法,包括嘈杂的20个问题游戏和一个笑话推荐任务。
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Multiple studies have focused on predicting the prospective popularity of an online document as a whole, without paying attention to the contributions of its individual parts. We introduce the task of proactively forecasting popularities of sentences within online news documents solely utilizing their natural language content. We model sentence-specific popularity forecasting as a sequence regression task. For training our models, we curate InfoPop, the first dataset containing popularity labels for over 1.7 million sentences from over 50,000 online news documents. To the best of our knowledge, this is the first dataset automatically created using streams of incoming search engine queries to generate sentence-level popularity annotations. We propose a novel transfer learning approach involving sentence salience prediction as an auxiliary task. Our proposed technique coupled with a BERT-based neural model exceeds nDCG values of 0.8 for proactive sentence-specific popularity forecasting. Notably, our study presents a non-trivial takeaway: though popularity and salience are different concepts, transfer learning from salience prediction enhances popularity forecasting. We release InfoPop and make our code publicly available: https://github.com/sayarghoshroy/InfoPopularity
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Speech systems are sensitive to accent variations. This is especially challenging in the Indian context, with an abundance of languages but a dearth of linguistic studies characterising pronunciation variations. The growing number of L2 English speakers in India reinforces the need to study accents and L1-L2 interactions. We investigate the accents of Indian English (IE) speakers and report in detail our observations, both specific and common to all regions. In particular, we observe the phonemic variations and phonotactics occurring in the speakers' native languages and apply this to their English pronunciations. We demonstrate the influence of 18 Indian languages on IE by comparing the native language pronunciations with IE pronunciations obtained jointly from existing literature studies and phonetically annotated speech of 80 speakers. Consequently, we are able to validate the intuitions of Indian language influences on IE pronunciations by justifying pronunciation rules from the perspective of Indian language phonology. We obtain a comprehensive description in terms of universal and region-specific characteristics of IE, which facilitates accent conversion and adaptation of existing ASR and TTS systems to different Indian accents.
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In molecular research, simulation \& design of molecules are key areas with significant implications for drug development, material science, and other fields. Current classical computational power falls inadequate to simulate any more than small molecules, let alone protein chains on hundreds of peptide. Therefore these experiment are done physically in wet-lab, but it takes a lot of time \& not possible to examine every molecule due to the size of the search area, tens of billions of dollars are spent every year in these research experiments. Molecule simulation \& design has lately advanced significantly by machine learning models, A fresh perspective on the issue of chemical synthesis is provided by deep generative models for graph-structured data. By optimising differentiable models that produce molecular graphs directly, it is feasible to avoid costly search techniques in the discrete and huge space of chemical structures. But these models also suffer from computational limitations when dimensions become huge and consume huge amount of resources. Quantum Generative machine learning in recent years have shown some empirical results promising significant advantages over classical counterparts.
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Developing and least developed countries face the dire challenge of ensuring that each child in their country receives required doses of vaccination, adequate nutrition and proper medication. International agencies such as UNICEF, WHO and WFP, among other organizations, strive to find innovative solutions to determine which child has received the benefits and which have not. Biometric recognition systems have been sought out to help solve this problem. To that end, this report establishes a baseline accuracy of a commercial contactless palmprint recognition system that may be deployed for recognizing children in the age group of one to five years old. On a database of contactless palmprint images of one thousand unique palms from 500 children, we establish SOTA authentication accuracy of 90.85% @ FAR of 0.01%, rank-1 identification accuracy of 99.0% (closed set), and FPIR=0.01 @ FNIR=0.3 for open-set identification using PalmMobile SDK from Armatura.
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Selective classification involves identifying the subset of test samples that a model can classify with high accuracy, and is important for applications such as automated medical diagnosis. We argue that this capability of identifying uncertain samples is valuable for training classifiers as well, with the aim of building more accurate classifiers. We unify these dual roles by training a single auxiliary meta-network to output an importance weight as a function of the instance. This measure is used at train time to reweight training data, and at test-time to rank test instances for selective classification. A second, key component of our proposal is the meta-objective of minimizing dropout variance (the variance of classifier output when subjected to random weight dropout) for training the metanetwork. We train the classifier together with its metanetwork using a nested objective of minimizing classifier loss on training data and meta-loss on a separate meta-training dataset. We outperform current state-of-the-art on selective classification by substantial margins--for instance, upto 1.9% AUC and 2% accuracy on a real-world diabetic retinopathy dataset. Finally, our meta-learning framework extends naturally to unsupervised domain adaptation, given our unsupervised variance minimization meta-objective. We show cumulative absolute gains of 3.4% / 3.3% accuracy and AUC over the other baselines in domain shift settings on the Retinopathy dataset using unsupervised domain adaptation.
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