Deep learning methods have contributed substantially to the rapid advancement of medical image segmentation, the quality of which relies on the suitable design of loss functions. Popular loss functions, including the cross-entropy and dice losses, often fall short of boundary detection, thereby limiting high-resolution downstream applications such as automated diagnoses and procedures. We developed a novel loss function that is tailored to reflect the boundary information to enhance the boundary detection. As the contrast between segmentation and background regions along the classification boundary naturally induces heterogeneity over the pixels, we propose the piece-wise two-sample t-test augmented (PTA) loss that is infused with the statistical test for such heterogeneity. We demonstrate the improved boundary detection power of the PTA loss compared to benchmark losses without a t-test component.
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超声(US)广泛用于实时成像,无辐射和便携性的优势。在临床实践中,分析和诊断通常依赖于美国序列,而不是单个图像来获得动态的解剖信息。对于新手来说,这是一项挑战,因为使用患者的足够视频进行练习是临床上不可行的。在本文中,我们提出了一个新颖的框架,以综合高保真美国视频。具体而言,合成视频是通过基于给定驾驶视频的动作来动画源内容图像来生成的。我们的亮点是三倍。首先,利用自我监督学习的优势,我们提出的系统以弱监督的方式进行了培训,以进行关键点检测。然后,这些关键点为处理美国视频中的复杂动态动作提供了重要信息。其次,我们使用双重解码器将内容和纹理学习解除,以有效地减少模型学习难度。最后,我们采用了对抗性训练策略,并采用了GAN损失,以进一步改善生成的视频的清晰度,从而缩小了真实和合成视频之间的差距。我们在具有高动态运动的大型内部骨盆数据集上验证我们的方法。广泛的评估指标和用户研究证明了我们提出的方法的有效性。
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在本文中,我们考虑了在规避风险的标准下线性收益的上下文多臂强盗问题。在每个回合中,每个手臂都会揭示上下文,决策者选择一只手臂拉动并获得相应的奖励。特别是,我们将均值变化视为风险标准,最好的组是具有最大均值奖励的均值。我们将汤普森采样算法应用于脱节模型,并为提出算法的变体提供全面的遗憾分析。对于$ t $ rounds,$ k $ Actions和$ d $ - 维功能向量,我们证明了$ o((1+ \ rho+\ frac {1} {1} {\ rho}){\ rho})d \ ln t \ ln t \ ln的遗憾。 \ frac {k} {\ delta} \ sqrt {d k t^{1+2 \ epsilon} \ ln \ frac {k} {\ delta} \ frac {1} {\ epsilon}} $ 1 - \ \ delta $在带有风险公差$ \ rho $的均值方差标准下,对于任何$ 0 <\ epsilon <\ frac {1} {2} $,$ 0 <\ delta <1 $。我们提出的算法的经验性能通过投资组合选择问题来证明。
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自然语言处理(NLP)通过分析社交媒体或新闻媒体的文本来证明支持财务决策的巨大潜力。在这项工作中,我们建立了一个平台,可以系统地研究NLP股票自动交易算法。与以前的工作相反,我们的平台具有三个功能:(1)我们为每个特定股票提供财务新闻。 (2)我们为每种股票提供各种股票因素。 (3)我们评估了更多与财务相关的指标的绩效。这样的设计使我们能够在更现实的环境中开发和评估NLP库存自动交易算法。除了设计评估平台和数据集集合外,我们还通过提出一个系统来自动从各种输入信息中学习良好的功能表示形式来做出技术贡献。我们算法的关键是一种称为语义角色标签池(SRLP)的方法,该方法利用语义角色标签(SRL)来创建每个新闻段的紧凑表示。基于SRLP,我们进一步纳入了其他股票因素以进行最终预测。此外,我们提出了一种基于SRLP的自我监督的学习策略,以增强系统的分布概括性能。通过我们的实验研究,我们表明所提出的方法可以实现更好的性能,并胜过所有基本线的年度回报率,以及CSI300指数和XIN9指数的最大减收率。我们的ASTOCK数据集和代码可在https://github.com/jinanzou/astock上找到。
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超声检查是乳腺癌诊断的重要常规检查,这是由于其无创,无辐射和低成本的特性。但是,由于其固有的局限性,乳腺癌的诊断准确性仍然受到限制。如果我们可以通过乳房超声图像(BUS)精确诊断乳腺癌,那将是一个巨大的成功。已经提出了许多基于学习的计算机辅助诊断方法来实现乳腺癌诊断/病变分类。但是,其中大多数需要预定的ROI,然后对ROI内的病变进行分类。常规的分类骨架,例如VGG16和RESNET50,可以在没有ROI要求的情况下获得有希望的分类结果。但是这些模型缺乏解释性,因此限制了它们在临床实践中的使用。在这项研究中,我们提出了一种具有可解释特征表示的超声图像中乳腺癌诊断的新型无ROI模型。我们利用解剖学的先验知识,即恶性肿瘤和良性肿瘤在不同的组织层之间具有不同的空间关系,并提出了悬停转换器来提出这种先验知识。提出的悬停式跨界块水平和垂直地提取层间和层内空间信息。我们进行并释放一个开放的数据集GDPH&SYSUCC,以用于公共汽车中的乳腺癌诊断。通过与四个基于CNN的模型和两个Vision Transformer模型进行比较,通过五倍的交叉验证来评估所提出的模型。它通过最佳模型可解释性实现最新的分类性能。同时,我们提出的模型在仅给出一张公交图像时,在乳腺癌诊断方面优于两名高级超声检查员。
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变压器模型已经取得了有希望的自然语言处理(NLP)任务,包括提取问题应答(QA)。 NLP任务中使用的通用变压器编码器在所有层中处理上下文段落中所有输入令牌的隐藏状态。但是,与序列分类等其他任务不同,应答所提出的问题不一定需要上下文段落中的所有令牌。在此动机之后,我们提出了薄块撇子,这将在更高的隐藏层中略微浏览不必要的上下文,以改善和加速变压器性能。块撇屏的关键概念是识别必须进一步处理的上下文,并且可以在推理期间早期安全地丢弃的语言。批判性地,我们发现这些信息可以充分地从变压器模型内的自我注意重量得出。我们进一步将对应于下层的不必要位置对应的隐藏状态,实现了显着的推理时间加速。令我们惊讶的是,我们观察到这种方式修剪的模型优于他们的全尺寸对应物。 Block-Skim在不同数据集上提高了QA模型的准确性,并在BERT-Base模型上实现了3次加速。
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To facilitate research on text generation, this paper presents a comprehensive and unified library, TextBox 2.0, focusing on the use of pre-trained language models (PLMs). To be comprehensive, our library covers $13$ common text generation tasks and their corresponding $83$ datasets and further incorporates $45$ PLMs covering general, translation, Chinese, dialogue, controllable, distilled, prompting, and lightweight PLMs. We also implement $4$ efficient training strategies and provide $4$ generation objectives for pre-training new PLMs from scratch. To be unified, we design the interfaces to support the entire research pipeline (from data loading to training and evaluation), ensuring that each step can be fulfilled in a unified way. Despite the rich functionality, it is easy to use our library, either through the friendly Python API or command line. To validate the effectiveness of our library, we conduct extensive experiments and exemplify four types of research scenarios. The project is released at the link: https://github.com/RUCAIBox/TextBox.
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Generative models have been widely applied to solve extractive tasks, where parts of the input is extracted to form the desired output, and achieved significant success. For example, in extractive question answering (QA), generative models have constantly yielded state-of-the-art results. In this work, we identify the issue of tokenization inconsistency that is commonly neglected in training these models. This issue damages the extractive nature of these tasks after the input and output are tokenized inconsistently by the tokenizer, and thus leads to performance drop as well as hallucination. We propose a simple yet effective fix to this issue and conduct a case study on extractive QA. We show that, with consistent tokenization, the model performs better in both in-domain and out-of-domain datasets, with a notable average of +1.7 F2 gain when a BART model is trained on SQuAD and evaluated on 8 QA datasets. Further, the model converges faster, and becomes less likely to generate out-of-context answers. With these findings, we would like to call for more attention on how tokenization should be done when solving extractive tasks and recommend applying consistent tokenization during training.
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There has been great progress in unifying various table-to-text tasks using a single encoder-decoder model trained via multi-task learning (Xie et al., 2022). However, existing methods typically encode task information with a simple dataset name as a prefix to the encoder. This not only limits the effectiveness of multi-task learning, but also hinders the model's ability to generalize to new domains or tasks that were not seen during training, which is crucial for real-world applications. In this paper, we propose compositional task configurations, a set of prompts prepended to the encoder to improve cross-task generalization of unified models. We design the task configurations to explicitly specify the task type, as well as its input and output types. We show that this not only allows the model to better learn shared knowledge across different tasks at training, but also allows us to control the model by composing new configurations that apply novel input-output combinations in a zero-shot manner. We demonstrate via experiments over ten table-to-text tasks that our method outperforms the UnifiedSKG baseline by noticeable margins in both in-domain and zero-shot settings, with average improvements of +0.5 and +12.6 from using a T5-large backbone, respectively.
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Image-text retrieval (ITR) is a challenging task in the field of multimodal information processing due to the semantic gap between different modalities. In recent years, researchers have made great progress in exploring the accurate alignment between image and text. However, existing works mainly focus on the fine-grained alignment between image regions and sentence fragments, which ignores the guiding significance of context background information. Actually, integrating the local fine-grained information and global context background information can provide more semantic clues for retrieval. In this paper, we propose a novel Hierarchical Graph Alignment Network (HGAN) for image-text retrieval. First, to capture the comprehensive multimodal features, we construct the feature graphs for the image and text modality respectively. Then, a multi-granularity shared space is established with a designed Multi-granularity Feature Aggregation and Rearrangement (MFAR) module, which enhances the semantic corresponding relations between the local and global information, and obtains more accurate feature representations for the image and text modalities. Finally, the ultimate image and text features are further refined through three-level similarity functions to achieve the hierarchical alignment. To justify the proposed model, we perform extensive experiments on MS-COCO and Flickr30K datasets. Experimental results show that the proposed HGAN outperforms the state-of-the-art methods on both datasets, which demonstrates the effectiveness and superiority of our model.
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