多类概率估计是估计属于类协变量信息的数据点的条件概率的问题。它在统计分析和数据科学中有广泛的应用。最近,已经开发了一类加权支持矢量机(WSVM),以通过$ k $ class问题的合奏学习来估计类概率(Wu,Zhang and Liu,2010; Wang,Zhang和Wu,2019年),其中$ K $是类的数量。估计器具有强大的概率估计,并实现了高精度,但是它们的学习是通过成对耦合实施的,这需要$ k $中的多项式时间。在本文中,我们提出了两种新的学习方案,即基线学习和一vs-all(OVA)学习,以进一步提高计算效率和估计准确性的WSVM。特别是,基线学习具有最佳的计算复杂性,因为它在$ k $中是线性的。尽管在计算方面不是最有效的,但OVA在比较的所有程序中提供了最佳的估计准确性。最终的估计器是无分布的,并且显示出一致的。我们进一步进行广泛的数值实验以证明有限的样本性能。
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尽管最近在图像翻译方面进行了显着进展,但具有多种差异对象的复杂场景仍然是一个具有挑战性的问题。因为翻译的图像具有低保真度和微小对象,更少,并在对象识别中获得不满意的性能。如果图像的彻底对象感知(即,边界框,类别和掩码)作为先验知识,则在图像转换过程中将难以跟踪每个对象的样式转换。我们提出了基于Panoptic的对象样式对齐生成的对抗生成的对抗网络(POSA-GAN),用于图像到图像 - 图像到图像转换,以及一个紧凑的Panoptic semation数据集。 Panoptic分割模型用于提取Panoptic-Level感知(即,除去图像中的重叠的前景对象实例和背景语义区域)。这用于指导从目标域的样式空间采样的输入域图像和对象样式代码的对象内容代码之间的对齐。进一步转换样式对齐的对象表示以获得更高保真对象生成的精确边界布局。与不同的竞争方法系统的系统进行了系统地进行了系统地进行了系统地进行了系统地进行了比较,并对翻译图像的图像质量和物体识别性能进行了显着改善。
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运动估计是用于评估目标器官解剖学和功能的动态医学图像处理的基本步骤。然而,通过评估局部图像相似性通过评估局部图像相似性优化运动场的基于图像的运动估计方法,易于产生令人难以置信的估计,尤其是在大运动的情况下。在这项研究中,我们提供了一种新颖的稀疏密度(DSD)的运动估计框架,其包括两个阶段。在第一阶段,我们处理原始密集图像以提取稀疏地标以表示目标器官解剖拓扑,并丢弃对运动估计不必要的冗余信息。为此目的,我们介绍一个无监督的3D地标检测网络,以提取用于目标器官运动估计的空间稀疏但代表性的地标。在第二阶段,我们从两个不同时间点的两个图像的提取稀疏地标的稀疏运动位移得出。然后,我们通过将稀疏地标位移突出回致密图像域,呈现运动重建网络来构造运动场。此外,我们从我们的两级DSD框架中使用估计的运动场作为初始化,并提高轻量级且有效的迭代优化中的运动估计质量。我们分别评估了两种动态医学成像任务的方法,分别为模型心脏运动和肺呼吸运动。与现有的比较方法相比,我们的方法产生了出色的运动估计精度。此外,广泛的实验结果表明,我们的解决方案可以提取良好代表性解剖标志,而无需手动注释。我们的代码在线公开提供。
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概率生成模型对科学建模具有吸引力,因为它们的推论参数可用于生成假设和设计实验。这要求学习的模型提供了对输入数据的准确表示,并产生一个潜在空间,该空间有效地预测了与科学问题相关的结果。监督的变异自动编码器(SVAE)以前已用于此目的,在此目的中,精心设计的解码器可以用作可解释的生成模型,而监督目标可确保预测性潜在表示。不幸的是,监督的目标迫使编码器学习与生成后验分布有偏见的近似,这在科学模型中使用时使生成参数不可靠。由于通常用于评估模型性能的重建损失,因此该问题仍未被发现。我们通过开发一个二阶监督框架(SOS-VAE)来解决这个以前未报告的问题,该框架影响解码器诱导预测潜在的代表。这样可以确保关联的编码器保持可靠的生成解释。我们扩展了此技术,以使用户能够在生成参数中折叠以提高预测性能,并充当SVAE和我们的新SOS-VAE之间的中间选择。我们还使用这种方法来解决在组合来自多个科学实验的录音时经常出现的缺失数据问题。我们使用合成数据和电生理记录来证明这些发展的有效性,重点是如何使用我们学到的表示形式来设计科学实验。
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数字商务泛化的黑暗面是欺诈尝试的增加。为防止任何类型的攻击,现代最先进的欺诈检测系统现在嵌入机器学习(ML)模块。这种模块的概念仅在研究水平上传达,论文主要关注孤立的基准数据集和度量的结果。但研究只是旅程的一部分,前面是业务问题的正确制定以及数据集合,然后是实际集成。在本文中,我们对该过程进行了更广泛的愿景,就转让学习进行欺诈检测,从企业进行研究,回到业务。
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Masked image modeling (MIM) performs strongly in pre-training large vision Transformers (ViTs). However, small models that are critical for real-world applications cannot or only marginally benefit from this pre-training approach. In this paper, we explore distillation techniques to transfer the success of large MIM-based pre-trained models to smaller ones. We systematically study different options in the distillation framework, including distilling targets, losses, input, network regularization, sequential distillation, etc, revealing that: 1) Distilling token relations is more effective than CLS token- and feature-based distillation; 2) An intermediate layer of the teacher network as target perform better than that using the last layer when the depth of the student mismatches that of the teacher; 3) Weak regularization is preferred; etc. With these findings, we achieve significant fine-tuning accuracy improvements over the scratch MIM pre-training on ImageNet-1K classification, using all the ViT-Tiny, ViT-Small, and ViT-base models, with +4.2%/+2.4%/+1.4% gains, respectively. Our TinyMIM model of base size achieves 52.2 mIoU in AE20K semantic segmentation, which is +4.1 higher than the MAE baseline. Our TinyMIM model of tiny size achieves 79.6% top-1 accuracy on ImageNet-1K image classification, which sets a new record for small vision models of the same size and computation budget. This strong performance suggests an alternative way for developing small vision Transformer models, that is, by exploring better training methods rather than introducing inductive biases into architectures as in most previous works. Code is available at https://github.com/OliverRensu/TinyMIM.
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In this paper, we propose a robust 3D detector, named Cross Modal Transformer (CMT), for end-to-end 3D multi-modal detection. Without explicit view transformation, CMT takes the image and point clouds tokens as inputs and directly outputs accurate 3D bounding boxes. The spatial alignment of multi-modal tokens is performed implicitly, by encoding the 3D points into multi-modal features. The core design of CMT is quite simple while its performance is impressive. CMT obtains 73.0% NDS on nuScenes benchmark. Moreover, CMT has a strong robustness even if the LiDAR is missing. Code will be released at https://github.com/junjie18/CMT.
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Dataset distillation has emerged as a prominent technique to improve data efficiency when training machine learning models. It encapsulates the knowledge from a large dataset into a smaller synthetic dataset. A model trained on this smaller distilled dataset can attain comparable performance to a model trained on the original training dataset. However, the existing dataset distillation techniques mainly aim at achieving the best trade-off between resource usage efficiency and model utility. The security risks stemming from them have not been explored. This study performs the first backdoor attack against the models trained on the data distilled by dataset distillation models in the image domain. Concretely, we inject triggers into the synthetic data during the distillation procedure rather than during the model training stage, where all previous attacks are performed. We propose two types of backdoor attacks, namely NAIVEATTACK and DOORPING. NAIVEATTACK simply adds triggers to the raw data at the initial distillation phase, while DOORPING iteratively updates the triggers during the entire distillation procedure. We conduct extensive evaluations on multiple datasets, architectures, and dataset distillation techniques. Empirical evaluation shows that NAIVEATTACK achieves decent attack success rate (ASR) scores in some cases, while DOORPING reaches higher ASR scores (close to 1.0) in all cases. Furthermore, we conduct a comprehensive ablation study to analyze the factors that may affect the attack performance. Finally, we evaluate multiple defense mechanisms against our backdoor attacks and show that our attacks can practically circumvent these defense mechanisms.
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Blind image quality assessment (BIQA) remains challenging due to the diversity of distortion and image content variation, which complicate the distortion patterns crossing different scales and aggravate the difficulty of the regression problem for BIQA. However, existing BIQA methods often fail to consider multi-scale distortion patterns and image content, and little research has been done on learning strategies to make the regression model produce better performance. In this paper, we propose a simple yet effective Progressive Multi-Task Image Quality Assessment (PMT-IQA) model, which contains a multi-scale feature extraction module (MS) and a progressive multi-task learning module (PMT), to help the model learn complex distortion patterns and better optimize the regression issue to align with the law of human learning process from easy to hard. To verify the effectiveness of the proposed PMT-IQA model, we conduct experiments on four widely used public datasets, and the experimental results indicate that the performance of PMT-IQA is superior to the comparison approaches, and both MS and PMT modules improve the model's performance.
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Automatic music generation with artificial intelligence typically requires a large amount of data which is hard to obtain for many less common genres and musical instruments. To tackle this issue, we present ongoing work and preliminary findings on the possibility for deep models to transfer knowledge from language to music, by finetuning large language models pre-trained on a massive text corpus on only hundreds of MIDI files of drum performances. We show that by doing so, one of the largest, state-of-the-art models (GPT3) is capable of generating reasonable drum grooves, while models that are not pre-trained (Transformer) shows no such ability beyond naive repetition. Evaluating generated music is a challenging task, more so is evaluating drum grooves with little precedence in literature. Hence, we propose a tailored structural evaluation method and analyze drum grooves produced by GPT3 compared to those played by human professionals, exposing the strengths and weaknesses of such generation by language-to-music transfer. Our findings suggest that language-to-music transfer learning with large language models is viable and promising.
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