我们考虑随机环境中在线线性回归的问题。我们派生了在线岭回归和前向算法的高概率遗憾。这使我们能够更准确地比较在线回归算法并消除有界观测和预测的假设。我们的研究由于其增强的界限和鲁棒性对正则化参数而代替脊，所以提出了前向算法的倡导者。此外，我们解释了如何将其集成在涉及线性函数近似的算法中以消除界限假设，而不会恶化理论界限。我们在线性强盗设置展示了这种修改，其中它产生了改进的遗憾范围。最后，我们提供数字实验来说明我们的结果并赞同我们的直觉。

The number of international benchmarking competitions is steadily increasing in various fields of machine learning (ML) research and practice. So far, however, little is known about the common practice as well as bottlenecks faced by the community in tackling the research questions posed. To shed light on the status quo of algorithm development in the specific field of biomedical imaging analysis, we designed an international survey that was issued to all participants of challenges conducted in conjunction with the IEEE ISBI 2021 and MICCAI 2021 conferences (80 competitions in total). The survey covered participants' expertise and working environments, their chosen strategies, as well as algorithm characteristics. A median of 72% challenge participants took part in the survey. According to our results, knowledge exchange was the primary incentive (70%) for participation, while the reception of prize money played only a minor role (16%). While a median of 80 working hours was spent on method development, a large portion of participants stated that they did not have enough time for method development (32%). 25% perceived the infrastructure to be a bottleneck. Overall, 94% of all solutions were deep learning-based. Of these, 84% were based on standard architectures. 43% of the respondents reported that the data samples (e.g., images) were too large to be processed at once. This was most commonly addressed by patch-based training (69%), downsampling (37%), and solving 3D analysis tasks as a series of 2D tasks. K-fold cross-validation on the training set was performed by only 37% of the participants and only 50% of the participants performed ensembling based on multiple identical models (61%) or heterogeneous models (39%). 48% of the respondents applied postprocessing steps.

任何涉及一组随机变量的概率模型的主要用途是在其上运行推理和采样查询。经典概率模型中的推理查询是通过计算作为输入的事件的边际或条件概率的计算。当概率模型是顺序的时，涉及复杂语法的更复杂的边际推理查询可能会在计算语言学和NLP等领域中引起人们的关注。在这项工作中，我们解决了在隐藏的马尔可夫模型（HMMS）中计算无上下文语法（CFG）的可能性的问题。我们提供了一种动态算法，用于确切计算无上下文的语法类别的可能性。我们表明问题是NP-HARD，即使输入CFG的歧义性程度小于或等于2。然后我们提出了一种完全多项式随机近似方案（FPRAS）算法，以近似案例的可能性多项式结合的模棱两可的CFG。

检测新的多发性硬化症（MS）病变是该疾病进化的重要标志。基于学习的方法的适用性可以有效地自动化此任务。然而，缺乏带有新型病变的注释纵向数据是训练健壮和概括模型的限制因素。在这项工作中，我们描述了一条基于学习的管道，该管道解决了检测和细分新MS病变的挑战性任务。首先，我们建议使用单个时间点对在分割任务进行训练的模型中使用转移学习。因此，我们从更轻松的任务中利用知识，并为此提供更多注释的数据集。其次，我们提出了一种数据综合策略，以使用单个时间点扫描生成新的纵向时间点。通过这种方式，我们将检测模型预算到大型合成注释数据集上。最后，我们使用旨在模拟MRI中数据多样性的数据实践技术。通过这样做，我们增加了可用的小注释纵向数据集的大小。我们的消融研究表明，每个贡献都会提高分割精度。使用拟议的管道，我们获得了MSSEG2 MICCAI挑战中新的MS病变的分割和检测的最佳分数。

培训细节和数据集对于筏等最新的光流模型有多重要？它们会概括吗？为了探索这些问题，而不是开发新的模型，我们将重新访问三个突出的模型，即PWC-NET，IRR-PWC和RAFT，并采用一组常见的现代培训技术和数据集，并观察到显着的性能增长，证明了重要性和普遍性这些培训细节。我们新训练的PWC-NET和IRR-PWC模型显示出惊人的改进，与Sintel和Kitti 2015 Benchmarks相比，最高30％的结果与原始发布的结果相比。他们的表现胜过2015年Kitti的最新流程1D，而推断过程中的速度快3倍。我们新训练的筏子在2015年的Kitti上获得了4.31％的成绩，比写作时所有已发表的光流方法更准确。我们的结果表明，分析光流方法的性能提高时，分离模型，训练技术和数据集的贡献的好处。我们的源代码将公开可用。

我们提出了一种框架插值算法，该算法从两个输入图像中综合了具有大型内部运动的两个输入图像。最近的方法使用多个网络来估计光流或深度以及专用于框架合成的单独网络。这通常是复杂的，需要稀缺的光流或深度地面真相。在这项工作中，我们提出了一个单一的统一网络，该网络以多尺度的特征提取器为特色，该特征提取器在各个尺度上共享权重，并且可以单独从框架中训练。为了综合酥脆和令人愉悦的框架，我们建议使用革兰氏矩阵损失来优化我们的网络，从而衡量特征地图之间的相关差异。我们的方法优于XIPH大型运动基准的最先进方法。与使用感知损失的方法相比，我们还可以在Vimeo-90K，Middlebury和UCF101上获得更高的分数。我们研究了体重共享和培训的效果，该数据集的运动范围不断增加。最后，我们证明了模型在综合高质量和临时连贯的视频中的有效性，该视频在具有挑战性的近乎修复的照片数据集中。代码和预训练模型可在https://film-net.github.io上找到。

神经网络的学习过程中的梯度下降可以受到许多不稳定性的影响。雅可比的光谱密度是用于分析鲁棒性的关键组件。遵循Pennington等人的作品。，这种雅各比人使用自由概率理论的自由乘法卷积进行了建模。我们介绍了用于计算相关的频谱密度的可靠和非常快速的方法。该方法具有受控和验证的收敛性。我们的技术基于适应性的牛顿Raphson方案，通过寻找和链接吸引力的盆地：牛顿算法发现邻近下一到另一个到另一个到另一个到另一个的邻近levypad盆地和步骤。我们通过使用它来评估学习过程受网络深度，层宽度和初始化选择的影响：经验，我们的最终测试损失与我们的自由概率度量非常相关。

Deep autoencoder has been extensively used for anomaly detection. Training on the normal data, the autoencoder is expected to produce higher reconstruction error for the abnormal inputs than the normal ones, which is adopted as a criterion for identifying anomalies. However, this assumption does not always hold in practice. It has been observed that sometimes the autoencoder "generalizes" so well that it can also reconstruct anomalies well, leading to the miss detection of anomalies. To mitigate this drawback for autoencoder based anomaly detector, we propose to augment the autoencoder with a memory module and develop an improved autoencoder called memory-augmented autoencoder, i.e. MemAE. Given an input, MemAE firstly obtains the encoding from the encoder and then uses it as a query to retrieve the most relevant memory items for reconstruction. At the training stage, the memory contents are updated and are encouraged to represent the prototypical elements of the normal data. At the test stage, the learned memory will be fixed, and the reconstruction is obtained from a few selected memory records of the normal data. The reconstruction will thus tend to be close to a normal sample. Thus the reconstructed errors on anomalies will be strengthened for anomaly detection. MemAE is free of assumptions on the data type and thus general to be applied to different tasks. Experiments on various datasets prove the excellent generalization and high effectiveness of the proposed MemAE.

Fig. 1. Masked images and corresponding inpainted results using our partialconvolution based network.