使用显式密度建模的生成模型(例如,变形式自动码码器,基于流动的生成模型)涉及从已知分布的映射,例如,从已知分布中找到映射。高斯,到未知的输入分布。这通常需要搜索一类非线性函数(例如,由深神经网络表示)。在实践中有效,相关的运行时/内存成本可以迅速增加,通常是应用程序中所需性能的函数。我们提出了一个更便宜的(更简单)的策略来估算基于内核传输运算符中的已知结果的此映射。我们表明我们的配方能够实现高效的分布近似和采样,并提供令人惊讶的良好的经验性能,与强大的基线有利,但有很大的运行时储蓄。我们表明该算法在小样本大小设置(脑成像)中也表现良好。
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Link prediction is a crucial problem in graph-structured data. Due to the recent success of graph neural networks (GNNs), a variety of GNN-based models were proposed to tackle the link prediction task. Specifically, GNNs leverage the message passing paradigm to obtain node representation, which relies on link connectivity. However, in a link prediction task, links in the training set are always present while ones in the testing set are not yet formed, resulting in a discrepancy of the connectivity pattern and bias of the learned representation. It leads to a problem of dataset shift which degrades the model performance. In this paper, we first identify the dataset shift problem in the link prediction task and provide theoretical analyses on how existing link prediction methods are vulnerable to it. We then propose FakeEdge, a model-agnostic technique, to address the problem by mitigating the graph topological gap between training and testing sets. Extensive experiments demonstrate the applicability and superiority of FakeEdge on multiple datasets across various domains.
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胸部计算机断层扫描的气道分割在肺部疾病诊断中起着至关重要的作用。与手动分割相比,基于U-NET体系结构的计算机辅助气道分割更有效,更准确。在本文中,我们采用了由骰子损失功能训练的U $^2 $ -NET,以基于ATM'22提供的299次培训CT扫描,对多站点CT扫描的气道树进行建模。从训练中将派生的显着性概率图应用于验证数据以提取相应的气道树。该观察结果表明,大多数分割的气道树从准确性和连通性的角度表现出色。将诸如非航空区域标签和去除之类的改进应用于某些获得的气道树模型,以显示二进制结果的最大组成部分。
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链接预测(LP)已被认为是图形学习的重要任务,其广泛的实际应用。 LP的典型应用是为给定的源节点(例如朋友推荐)检索最高的评分邻居。这些服务希望具有很高的推理可伸缩性,以找到低潜伏期中许多候选节点的最高评分邻居。最近有两个流行的解码器主要用于计算节点嵌入的边缘得分:HadamArdMLP和DOT产品解码器。经过理论和经验分析后,我们发现HadamardMLP解码器通常对LP更有效。但是,HadamardMLP缺乏在大图上检索最高得分的邻居的可扩展性,因为据我们所知,并不存在算法来检索sublinearearightions中的HadamardMLP解码器的最高得分邻居。为了使HadamardMLP可扩展,我们建议使用手电筒算法加速HadamardMLP的最高得分邻居检索:一种弹性算法,该算法逐渐应用了具有适应性调整的查询嵌入的近似最大内部产品搜索(MIPS)技术。经验结果表明,手电筒在不牺牲效力的情况下将LP的推理速度提高了100倍以上。我们的工作为大规模LP应用程序铺平了道路,并通过大大加速其推断,并通过有效的HadamArdMLP解码器铺平了道路。
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尽管图神经网络(GNNS)已经证明了它们在处理非欧国人结构数据方面的功效,但由于多跳数据依赖性施加的可伸缩性约束,因此很难将它们部署在实际应用中。现有方法试图通过使用训练有素的GNN的标签训练多层感知器(MLP)来解决此可伸缩性问题。即使可以显着改善MLP的性能,但两个问题仍能阻止MLP的表现优于GNN并在实践中使用:图形结构信息的无知和对节点功能噪声的敏感性。在本文中,我们建议在图(NOSMOG)上学习噪声稳定结构感知的MLP,以克服挑战。具体而言,我们首先将节点内容与位置功能进行补充,以帮助MLP捕获图形结构信息。然后,我们设计了一种新颖的表示相似性蒸馏策略,以将结构节点相似性注入MLP。最后,我们介绍了对抗性功能的扩展,以确保稳定的学习能力噪声,并进一步提高性能。广泛的实验表明,在七个数据集中,NOSMOG在转导和归纳环境中均优于GNN和最先进的方法,同时保持竞争性推理效率。
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分子表示学习(MRL)是建立机器学习与化学科学之间联系的关键步骤。特别是,它将分子编码为保留分子结构和特征的数值向量,在其上可以执行下游任务(例如,属性预测)。最近,MRL取得了相当大的进步,尤其是在基于深的分子图学习方法中。在这项调查中,我们系统地回顾了这些基于图的分子表示技术。具体而言,我们首先介绍2D和3D图分子数据集的数据和功能。然后,我们总结了专门为MRL设计的方法,并将其分为四种策略。此外,我们讨论了MRL支持的一些典型化学应用。为了促进该快速发展领域的研究,我们还列出了论文中的基准和常用数据集。最后,我们分享我们对未来研究方向的想法。
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This paper focuses on designing efficient models with low parameters and FLOPs for dense predictions. Even though CNN-based lightweight methods have achieved stunning results after years of research, trading-off model accuracy and constrained resources still need further improvements. This work rethinks the essential unity of efficient Inverted Residual Block in MobileNetv2 and effective Transformer in ViT, inductively abstracting a general concept of Meta-Mobile Block, and we argue that the specific instantiation is very important to model performance though sharing the same framework. Motivated by this phenomenon, we deduce a simple yet efficient modern \textbf{I}nverted \textbf{R}esidual \textbf{M}obile \textbf{B}lock (iRMB) for mobile applications, which absorbs CNN-like efficiency to model short-distance dependency and Transformer-like dynamic modeling capability to learn long-distance interactions. Furthermore, we design a ResNet-like 4-phase \textbf{E}fficient \textbf{MO}del (EMO) based only on a series of iRMBs for dense applications. Massive experiments on ImageNet-1K, COCO2017, and ADE20K benchmarks demonstrate the superiority of our EMO over state-of-the-art methods, \eg, our EMO-1M/2M/5M achieve 71.5, 75.1, and 78.4 Top-1 that surpass \textbf{SoTA} CNN-/Transformer-based models, while trading-off the model accuracy and efficiency well.
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Supervised Question Answering systems (QA systems) rely on domain-specific human-labeled data for training. Unsupervised QA systems generate their own question-answer training pairs, typically using secondary knowledge sources to achieve this outcome. Our approach (called PIE-QG) uses Open Information Extraction (OpenIE) to generate synthetic training questions from paraphrased passages and uses the question-answer pairs as training data for a language model for a state-of-the-art QA system based on BERT. Triples in the form of <subject, predicate, object> are extracted from each passage, and questions are formed with subjects (or objects) and predicates while objects (or subjects) are considered as answers. Experimenting on five extractive QA datasets demonstrates that our technique achieves on-par performance with existing state-of-the-art QA systems with the benefit of being trained on an order of magnitude fewer documents and without any recourse to external reference data sources.
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Transformer has achieved impressive successes for various computer vision tasks. However, most of existing studies require to pretrain the Transformer backbone on a large-scale labeled dataset (e.g., ImageNet) for achieving satisfactory performance, which is usually unavailable for medical images. Additionally, due to the gap between medical and natural images, the improvement generated by the ImageNet pretrained weights significantly degrades while transferring the weights to medical image processing tasks. In this paper, we propose Bootstrap Own Latent of Transformer (BOLT), a self-supervised learning approach specifically for medical image classification with the Transformer backbone. Our BOLT consists of two networks, namely online and target branches, for self-supervised representation learning. Concretely, the online network is trained to predict the target network representation of the same patch embedding tokens with a different perturbation. To maximally excavate the impact of Transformer from limited medical data, we propose an auxiliary difficulty ranking task. The Transformer is enforced to identify which branch (i.e., online/target) is processing the more difficult perturbed tokens. Overall, the Transformer endeavours itself to distill the transformation-invariant features from the perturbed tokens to simultaneously achieve difficulty measurement and maintain the consistency of self-supervised representations. The proposed BOLT is evaluated on three medical image processing tasks, i.e., skin lesion classification, knee fatigue fracture grading and diabetic retinopathy grading. The experimental results validate the superiority of our BOLT for medical image classification, compared to ImageNet pretrained weights and state-of-the-art self-supervised learning approaches.
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Knowledge graph embedding (KGE), which maps entities and relations in a knowledge graph into continuous vector spaces, has achieved great success in predicting missing links in knowledge graphs. However, knowledge graphs often contain incomplete triples that are difficult to inductively infer by KGEs. To address this challenge, we resort to analogical inference and propose a novel and general self-supervised framework AnKGE to enhance KGE models with analogical inference capability. We propose an analogical object retriever that retrieves appropriate analogical objects from entity-level, relation-level, and triple-level. And in AnKGE, we train an analogy function for each level of analogical inference with the original element embedding from a well-trained KGE model as input, which outputs the analogical object embedding. In order to combine inductive inference capability from the original KGE model and analogical inference capability enhanced by AnKGE, we interpolate the analogy score with the base model score and introduce the adaptive weights in the score function for prediction. Through extensive experiments on FB15k-237 and WN18RR datasets, we show that AnKGE achieves competitive results on link prediction task and well performs analogical inference.
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