黑框模型的鲁棒性研究被认为是基于结构方程和从数据中学到的预测模型的数值模型的必要任务。这些研究必须评估模型的鲁棒性,以实现其输入的可能错误指定(例如,协变量转移)。通过不确定性定量(UQ)的棱镜对黑盒模型的研究通常基于涉及输入上施加的概率结构的灵敏度分析,而ML模型仅由观察到的数据构建。我们的工作旨在通过为这两个范式提供相关且易于使用的工具来统一UQ和ML可解释性方法。为了为鲁棒性研究提供一个通用且易于理解的框架,我们定义了依赖于概率指标之间的瓦斯汀距离的分位数约束和投影的输入信息的扰动,同时保留其依赖性结构。我们表明,可以通过分析解决这个扰动问题。通过等渗多项式近似确保规律性约束会导致更平滑的扰动,这在实践中可能更适合。从UQ和ML领域进行的实际案例研究的数值实验突出了此类研究的计算可行性,并提供了对黑盒模型鲁棒性的局部和全球见解,以输入扰动。
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在过去几年中,图像分析的工业和社会应用中,神经网络分类器的越来越常见使用令人印象深刻的进展。然而,这种方法对算法偏压敏感,即阳性预测的欠或过度表示或在图像的特定子组中的更高预测误差。然后,我们在本文中介绍了一种新的方法来发动基于神经网络的分类器中的算法偏压。我们的方法是神经网络架构不可知的和缩放到大规模训练的图像集。它确实只使用基于Wassersein-2的损失函数超载了基于Wasserstein-2的正则化术语,我们基于预测分布的Gateaux衍生物,我们使用新模型对特定输出预测的影响传播了特定输出预测的影响。该型号是算法的合理性,使我们可以使用标准随机梯度 - 下降策略来使用我们的正则损耗。它的良好行为是在参考成人人口普查,Mnist,Celeba数据集中进行评估。
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在本文中,我们提出了一种新的可解释性形式主义,旨在阐明测试集的每个输入变量如何影响机器学习模型的预测。因此,我们根据训练有素的机器学习决策规则提出了一个群体的解释性形式,它们是根据其对输入变量分布的可变性的反应。为了强调每个输入变量的影响,这种形式主义使用信息理论框架,该框架量化了基于熵投影的所有输入输出观测值的影响。因此,这是第一个统一和模型不可知的形式主义,使数据科学家能够解释输入变量之间的依赖性,它们对预测错误的影响以及它们对输出预测的影响。在大型样本案例中提供了熵投影的收敛速率。最重要的是,我们证明,计算框架中的解释具有低算法的复杂性,使其可扩展到现实生活中的大数据集。我们通过解释通过在各种数据集上使用XGBoost,随机森林或深层神经网络分类器(例如成人收入,MNIST,CELEBA,波士顿住房,IRIS以及合成的)上使用的复杂决策规则来说明我们的策略。最终,我们明确了基于单个观察结果的解释性策略石灰和摇摆的差异。可以通过使用自由分布的Python工具箱https://gems-ai.aniti.fr/来复制结果。
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Neural style transfer is a deep learning technique that produces an unprecedentedly rich style transfer from a style image to a content image and is particularly impressive when it comes to transferring style from a painting to an image. It was originally achieved by solving an optimization problem to match the global style statistics of the style image while preserving the local geometric features of the content image. The two main drawbacks of this original approach is that it is computationally expensive and that the resolution of the output images is limited by high GPU memory requirements. Many solutions have been proposed to both accelerate neural style transfer and increase its resolution, but they all compromise the quality of the produced images. Indeed, transferring the style of a painting is a complex task involving features at different scales, from the color palette and compositional style to the fine brushstrokes and texture of the canvas. This paper provides a solution to solve the original global optimization for ultra-high resolution images, enabling multiscale style transfer at unprecedented image sizes. This is achieved by spatially localizing the computation of each forward and backward passes through the VGG network. Extensive qualitative and quantitative comparisons show that our method produces a style transfer of unmatched quality for such high resolution painting styles.
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Neural networks trained on large datasets by minimizing a loss have become the state-of-the-art approach for resolving data science problems, particularly in computer vision, image processing and natural language processing. In spite of their striking results, our theoretical understanding about how neural networks operate is limited. In particular, what are the interpolation capabilities of trained neural networks? In this paper we discuss a theorem of Domingos stating that "every machine learned by continuous gradient descent is approximately a kernel machine". According to Domingos, this fact leads to conclude that all machines trained on data are mere kernel machines. We first extend Domingo's result in the discrete case and to networks with vector-valued output. We then study its relevance and significance on simple examples. We find that in simple cases, the "neural tangent kernel" arising in Domingos' theorem does provide understanding of the networks' predictions. Furthermore, when the task given to the network grows in complexity, the interpolation capability of the network can be effectively explained by Domingos' theorem, and therefore is limited. We illustrate this fact on a classic perception theory problem: recovering a shape from its boundary.
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任何相机的光学元件都会降低照片的清晰度,这是关键的视觉质量标准。该降解的特征是点传播函数(PSF),该函数取决于光的波长,并且在整个成像场中都是可变的。在本文中,我们提出了一个两步方案,以纠正单个RAW或JPEG图像中的光学畸变,即没有相机或镜头上任何事先信息。首先,我们估计当地的高斯模糊内核,以重叠斑块,并通过非盲脱毛技术锐化它们。基于数十个透镜的PSF的测量值,这些模糊内核被建模为由七个参数定义的RGB高斯人。其次,我们使用卷积神经网络去除其余的侧向色差(第一步中未考虑),该网络被训练,可将红色/绿色和蓝色/绿色残留图像最小化。关于合成图像和真实图像的实验表明,这两个阶段的组合产生了一种快速的最新盲目畸变补偿技术,该技术与商业非盲算法竞争。
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