本文介绍了针对非负矩阵分解的新的乘法更新,并使用$ \ beta $ -Divergence和两个因素之一的稀疏正则化(例如,激活矩阵)。众所周知,需要控制另一个因素(字典矩阵)的规范,以避免使用不良的公式。标准实践包括限制字典的列具有单位规范,这导致了非平凡的优化问题。我们的方法利用原始问题对等效规模不变的目标函数的优化进行了重新处理。从那里,我们得出了块状大量最小化算法,这些算法可为$ \ ell_ {1} $ - 正则化或更“激进的” log-regularization提供简单的乘法更新。与其他最先进的方法相反,我们的算法是通用的,因为它们可以应用于任何$ \ beta $ -Divergence(即任何$ \ beta $的任何值),并且它们具有融合保证。我们使用各种数据集报告了与现有的启发式和拉格朗日方法的数值比较:面部图像,音频谱图,高光谱数据和歌曲播放计数。我们表明,我们的方法获得了收敛时类似质量的溶液(相似的目标值),但CPU时间显着减少。
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本文提出了具有$ \ Beta $ -divercent objectivent函数的非负面矩阵分组(NMF)的新乘法更新。我们的新更新来自联合大修 - 最小化(MM)方案,其中包括在每次迭代的两个因素中构建了两个因素的辅助功能(客观函数的紧密上限)。这与经典方法相反,其中主要是针对每个因素导出的主要方法。与那种经典方法一样,我们的关节MM算法也导致乘法更新易于实现。然而,它们产生了显着的计算时间(适用于同样的良好解决方案),特别是对于一些$ \β$ - 重要的申请兴趣,如平方欧几里德距离和kullback-Leibler或Itakura-Saito分歧。我们使用不同数据集报告实验结果:面部图像,音频谱图,高光谱数据和歌曲播放计数。根据$ \ beta $和dataSet的值,我们的关节MM方法可以与经典交替方案相比,从大约13 \%$ 78 \%$产生CPU时间减少。
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We address the problem of unsupervised domain adaptation when the source domain differs from the target domain because of a shift in the distribution of a latent subgroup. When this subgroup confounds all observed data, neither covariate shift nor label shift assumptions apply. We show that the optimal target predictor can be non-parametrically identified with the help of concept and proxy variables available only in the source domain, and unlabeled data from the target. The identification results are constructive, immediately suggesting an algorithm for estimating the optimal predictor in the target. For continuous observations, when this algorithm becomes impractical, we propose a latent variable model specific to the data generation process at hand. We show how the approach degrades as the size of the shift changes, and verify that it outperforms both covariate and label shift adjustment.
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We introduce the Conditional Independence Regression CovariancE (CIRCE), a measure of conditional independence for multivariate continuous-valued variables. CIRCE applies as a regularizer in settings where we wish to learn neural features $\varphi(X)$ of data $X$ to estimate a target $Y$, while being conditionally independent of a distractor $Z$ given $Y$. Both $Z$ and $Y$ are assumed to be continuous-valued but relatively low dimensional, whereas $X$ and its features may be complex and high dimensional. Relevant settings include domain-invariant learning, fairness, and causal learning. The procedure requires just a single ridge regression from $Y$ to kernelized features of $Z$, which can be done in advance. It is then only necessary to enforce independence of $\varphi(X)$ from residuals of this regression, which is possible with attractive estimation properties and consistency guarantees. By contrast, earlier measures of conditional feature dependence require multiple regressions for each step of feature learning, resulting in more severe bias and variance, and greater computational cost. When sufficiently rich features are used, we establish that CIRCE is zero if and only if $\varphi(X) \perp \!\!\! \perp Z \mid Y$. In experiments, we show superior performance to previous methods on challenging benchmarks, including learning conditionally invariant image features.
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The detection and prevention of illegal fishing is critical to maintaining a healthy and functional ecosystem. Recent research on ship detection in satellite imagery has focused exclusively on performance improvements, disregarding detection efficiency. However, the speed and compute cost of vessel detection are essential for a timely intervention to prevent illegal fishing. Therefore, we investigated optimization methods that lower detection time and cost with minimal performance loss. We trained an object detection model based on a convolutional neural network (CNN) using a dataset of satellite images. Then, we designed two efficiency optimizations that can be applied to the base CNN or any other base model. The optimizations consist of a fast, cheap classification model and a statistical algorithm. The integration of the optimizations with the object detection model leads to a trade-off between speed and performance. We studied the trade-off using metrics that give different weight to execution time and performance. We show that by using a classification model the average precision of the detection model can be approximated to 99.5% in 44% of the time or to 92.7% in 25% of the time.
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Quantifying the deviation of a probability distribution is challenging when the target distribution is defined by a density with an intractable normalizing constant. The kernel Stein discrepancy (KSD) was proposed to address this problem and has been applied to various tasks including diagnosing approximate MCMC samplers and goodness-of-fit testing for unnormalized statistical models. This article investigates a convergence control property of the diffusion kernel Stein discrepancy (DKSD), an instance of the KSD proposed by Barp et al. (2019). We extend the result of Gorham and Mackey (2017), which showed that the KSD controls the bounded-Lipschitz metric, to functions of polynomial growth. Specifically, we prove that the DKSD controls the integral probability metric defined by a class of pseudo-Lipschitz functions, a polynomial generalization of Lipschitz functions. We also provide practical sufficient conditions on the reproducing kernel for the stated property to hold. In particular, we show that the DKSD detects non-convergence in moments with an appropriate kernel.
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Can continuous diffusion models bring the same performance breakthrough on natural language they did for image generation? To circumvent the discrete nature of text data, we can simply project tokens in a continuous space of embeddings, as is standard in language modeling. We propose Self-conditioned Embedding Diffusion, a continuous diffusion mechanism that operates on token embeddings and allows to learn flexible and scalable diffusion models for both conditional and unconditional text generation. Through qualitative and quantitative evaluation, we show that our text diffusion models generate samples comparable with those produced by standard autoregressive language models - while being in theory more efficient on accelerator hardware at inference time. Our work paves the way for scaling up diffusion models for text, similarly to autoregressive models, and for improving performance with recent refinements to continuous diffusion.
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当歌曲创作或演奏时,歌手/词曲作者通常会出现通过它表达感受或情感的意图。对于人类而言,将音乐作品或表演中的情感与观众的主观感知相匹配可能会非常具有挑战性。幸运的是,此问题的机器学习方法更简单。通常,它需要一个数据集,从该数据集中提取音频功能以将此信息呈现给数据驱动的模型,从而又将训练以预测给定歌曲与目标情绪匹配的概率是什么。在本文中,我们研究了最近出版物中最常见的功能和模型来解决此问题,揭示了哪些最适合在无伴奏歌曲中识别情感。
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机器人的感知目前处于在有效的潜在空间中运行的现代方法与数学建立的经典方法之间的跨道路,并提供了可解释的,可信赖的结果。在本文中,我们引入了卷积的贝叶斯内核推理(Convbki)层,该层在可分离的卷积层中明确执行贝叶斯推断,以同时提高效率,同时保持可靠性。我们将层应用于3D语义映射的任务,在该任务中,我们可以实时学习激光雷达传感器信息的语义几何概率分布。我们根据KITTI数据集的最新语义映射算法评估我们的网络,并通过类似的语义结果证明了延迟的提高。
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可见的红外人员重新识别(REID)旨在认识到RGB和IR摄像机网络中的同一个人。一些深度学习(DL)模型已直接纳入了两种模式,以在联合表示空间中区分人。但是,由于RGB和IR模式之间数据分布的较大域转移,因此这个跨模式的REID问题仍然具有挑战性。 %本文引入了一种新的方法,用于创建中间虚拟域,该域在训练过程中充当两个主要领域(即RGB和IR模式)之间的桥梁。该中间域被视为在测试时间无法获得的特权信息(PI),并允许将此跨模式匹配任务制定为在特权信息(LUPI)下学习的问题。我们设计了一种新方法,以在可见的和红外域之间生成图像,这些方法提供了其他信息,以通过中间域的适应来训练深层REID模型。特别是,通过在训练过程中采用无色和多步三重态损失目标,我们的方法提供了通用的特征表示空间,这些空间对大型可见的红外域移动具有牢固的功能。 %关于挑战性可见红外REID数据集的实验结果表明,我们提出的方法始终提高匹配的准确性,而在测试时没有任何计算开销。该代码可在:\ href {https://github.com/alehdaghi/cross-modal-re-id-iid-via-lupi} {https://github.com/alehdaghi/alehdaghi/cross-modal-re-re-id-i-id--i- id-i--i- id-id-i--i--via-lupi} { Via-Lupi}
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