本文调查了股票回购,特别是分享回购公告。它解决了如何识别此类公告,股票回购的超额回报以及股票回购公告后的回报的预测。我们说明了两种NLP方法,用于自动检测股票回购公告。即使有少量的培训数据,我们也可以达到高达90%的准确性。该论文利用这些NLP方法生成一个由57,155个股票回购公告组成的大数据集。通过分析该数据集,本论文的目的是表明大多数宣布回购的公司的大多数公司都表现不佳。但是,少数公司的表现极大地超过了MSCI世界。当查看所有公司的平均值时,这种重要的表现过高会导致净收益。如果根据公司的规模调整了基准指数,则平均表现过高,并且大多数表现不佳。但是,发现宣布股票回购的公司至少占其市值的1%,即使使用调整后的基准,也平均交付了显着的表现。还发现,在危机时期宣布股票回购的公司比整个市场更好。此外,生成的数据集用于训练72个机器学习模型。通过此,它能够找到许多可以达到高达77%并产生大量超额回报的策略。可以在六个不同的时间范围内改善各种性能指标,并确定明显的表现。这是通过训练多个模型的不同任务和时间范围以及结合这些不同模型的方法来实现的,从而通过融合弱学习者来产生重大改进,以创造一个强大的学习者。
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Artificial intelligence (AI) technologies revolutionize vast fields of society. Humans using these systems are likely to expect them to work in a potentially hyperrational manner. However, in this study, we show that some AI systems, namely large language models (LLMs), exhibit behavior that strikingly resembles human-like intuition - and the many cognitive errors that come with them. We use a state-of-the-art LLM, namely the latest iteration of OpenAI's Generative Pre-trained Transformer (GPT-3.5), and probe it with the Cognitive Reflection Test (CRT) as well as semantic illusions that were originally designed to investigate intuitive decision-making in humans. Our results show that GPT-3.5 systematically exhibits "machine intuition," meaning that it produces incorrect responses that are surprisingly equal to how humans respond to the CRT as well as to semantic illusions. We investigate several approaches to test how sturdy GPT-3.5's inclination for intuitive-like decision-making is. Our study demonstrates that investigating LLMs with methods from cognitive science has the potential to reveal emergent traits and adjust expectations regarding their machine behavior.
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对卷积神经网络(CNN)的对抗性攻击的存在质疑这种模型对严重应用的适合度。攻击操纵输入图像,使得错误分类是在对人类观察者看上去正常的同时唤起的 - 因此它们不容易被检测到。在不同的上下文中,CNN隐藏层的反向传播激活(对给定输入的“特征响应”)有助于可视化人类“调试器” CNN“在计算其输出时对CNN”的看法。在这项工作中,我们提出了一种新颖的检测方法,以防止攻击。我们通过在特征响应中跟踪对抗扰动来做到这一点,从而可以使用平均局部空间熵自动检测。该方法不会改变原始的网络体系结构,并且完全可以解释。实验证实了我们对在Imagenet训练的大规模模型的最新攻击方法的有效性。
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相关光和电子显微镜是研究细胞内部结构的强大工具。它结合了相关光(LM)和电子(EM)显微镜信息的相互益处。但是,将LM叠加到EM图像以将功能分配给结构信息的经典方法受到LM图像中可见的结构细节的巨大差异的阻碍。本文旨在研究一种优化方法,我们称之为EM引导的反卷积。它试图将荧光标记的结构自动分配给EM图像中可见的细节,以弥合两种成像模式之间的分辨率和特异性的间隙。
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随着Covid-19在世界范围内的传播,需要快速,精确的自动分诊机制,以减少人类的努力,例如用于基于图像的诊断。尽管文献在这个方向上显示出了有希望的努力,但报告的结果并未考虑在不同情况下获得的CT扫描的可变性,因此,渲染模型不适合使用,例如使用例如使用例如不同的扫描仪技术。虽然现在可以使用PCR测试有效地进行COVID-19诊断,但该用例却例证了一种方法来克服数据可变性问题以使医疗图像分析模型更广泛地适用。在本文中,我们使用COVID-19诊断的示例明确解决了可变性问题,并提出了一种新颖的生成方法,旨在消除例如成像技术同时通过利用深度自动编码器的想法来同时引入CT扫描的最小变化。拟议的预性架构(PrepNet)(i)在多个CT扫描数据集上共同训练,(ii)能够提取改进的判别特征以改善诊断。三个公共数据集(SARS-COVID-2,UCSD COVID-CT,MOSMED)的实验结果表明,我们的模型将交叉数据集的概括提高了高达$ 11.84 $ $的百分比,尽管数据集绩效中的情况略有下降。
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In recent years, substantial progress has been achieved in learning-based reconstruction of 3D objects. At the same time, generative models were proposed that can generate highly realistic images. However, despite this success in these closely related tasks, texture reconstruction of 3D objects has received little attention from the research community and state-of-the-art methods are either limited to comparably low resolution or constrained experimental setups. A major reason for these limitations is that common representations of texture are inefficient or hard to interface for modern deep learning techniques. In this paper, we propose Texture Fields, a novel texture representation which is based on regressing a continuous 3D function parameterized with a neural network. Our approach circumvents limiting factors like shape discretization and parameterization, as the proposed texture representation is independent of the shape representation of the 3D object. We show that Texture Fields are able to represent high frequency texture and naturally blend with modern deep learning techniques. Experimentally, we find that Texture Fields compare favorably to state-of-the-art methods for conditional texture reconstruction of 3D objects and enable learning of probabilistic generative models for texturing unseen 3D models. We believe that Texture Fields will become an important building block for the next generation of generative 3D models.
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