通过离散采样观测来建模连续的动力系统是数据科学中的一个基本问题。通常,这种动力学是非本地过程随时间不可或缺的结果。因此,这些系统是用插差分化方程(IDE)建模的;构成积分和差分组件的微分方程的概括。例如,大脑动力学不是通过微分方程来准确模拟的,因为它们的行为是非马克维亚的,即动态是部分由历史决定的。在这里,我们介绍了神经IDE(NIDE),该框架使用神经网络建模IDE的普通和组成部分。我们在几个玩具和大脑活动数据集上测试NIDE,并证明NIDE的表现优于其他模型,包括神经ODE。这些任务包括时间外推,以及从看不见的初始条件中预测动态,我们在自由行为的小鼠中测试了全皮质活动记录。此外,我们表明,NIDE可以通过学识渊博的整体操作员将动力学分解为马尔可夫和非马克维亚成分,我们在氯胺酮的fMRI脑活动记录中测试了动力学。最后,整体操作员的整体提供了一个潜在空间,可深入了解潜在的动态,我们在宽阔的大脑成像记录上证明了这一点。总体而言,NIDE是一种新颖的方法,可以通过神经网络对复杂的非本地动力学进行建模。
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As language models (LMs) scale, they develop many novel behaviors, good and bad, exacerbating the need to evaluate how they behave. Prior work creates evaluations with crowdwork (which is time-consuming and expensive) or existing data sources (which are not always available). Here, we automatically generate evaluations with LMs. We explore approaches with varying amounts of human effort, from instructing LMs to write yes/no questions to making complex Winogender schemas with multiple stages of LM-based generation and filtering. Crowdworkers rate the examples as highly relevant and agree with 90-100% of labels, sometimes more so than corresponding human-written datasets. We generate 154 datasets and discover new cases of inverse scaling where LMs get worse with size. Larger LMs repeat back a dialog user's preferred answer ("sycophancy") and express greater desire to pursue concerning goals like resource acquisition and goal preservation. We also find some of the first examples of inverse scaling in RL from Human Feedback (RLHF), where more RLHF makes LMs worse. For example, RLHF makes LMs express stronger political views (on gun rights and immigration) and a greater desire to avoid shut down. Overall, LM-written evaluations are high-quality and let us quickly discover many novel LM behaviors.
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Purpose: The aim of this study was to demonstrate the utility of unsupervised domain adaptation (UDA) in automated knee osteoarthritis (OA) phenotype classification using a small dataset (n=50). Materials and Methods: For this retrospective study, we collected 3,166 three-dimensional (3D) double-echo steady-state magnetic resonance (MR) images from the Osteoarthritis Initiative dataset and 50 3D turbo/fast spin-echo MR images from our institute (in 2020 and 2021) as the source and target datasets, respectively. For each patient, the degree of knee OA was initially graded according to the MRI Osteoarthritis Knee Score (MOAKS) before being converted to binary OA phenotype labels. The proposed UDA pipeline included (a) pre-processing, which involved automatic segmentation and region-of-interest cropping; (b) source classifier training, which involved pre-training phenotype classifiers on the source dataset; (c) target encoder adaptation, which involved unsupervised adaption of the source encoder to the target encoder and (d) target classifier validation, which involved statistical analysis of the target classification performance evaluated by the area under the receiver operating characteristic curve (AUROC), sensitivity, specificity and accuracy. Additionally, a classifier was trained without UDA for comparison. Results: The target classifier trained with UDA achieved improved AUROC, sensitivity, specificity and accuracy for both knee OA phenotypes compared with the classifier trained without UDA. Conclusion: The proposed UDA approach improves the performance of automated knee OA phenotype classification for small target datasets by utilising a large, high-quality source dataset for training. The results successfully demonstrated the advantages of the UDA approach in classification on small datasets.
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As Artificial and Robotic Systems are increasingly deployed and relied upon for real-world applications, it is important that they exhibit the ability to continually learn and adapt in dynamically-changing environments, becoming Lifelong Learning Machines. Continual/lifelong learning (LL) involves minimizing catastrophic forgetting of old tasks while maximizing a model's capability to learn new tasks. This paper addresses the challenging lifelong reinforcement learning (L2RL) setting. Pushing the state-of-the-art forward in L2RL and making L2RL useful for practical applications requires more than developing individual L2RL algorithms; it requires making progress at the systems-level, especially research into the non-trivial problem of how to integrate multiple L2RL algorithms into a common framework. In this paper, we introduce the Lifelong Reinforcement Learning Components Framework (L2RLCF), which standardizes L2RL systems and assimilates different continual learning components (each addressing different aspects of the lifelong learning problem) into a unified system. As an instantiation of L2RLCF, we develop a standard API allowing easy integration of novel lifelong learning components. We describe a case study that demonstrates how multiple independently-developed LL components can be integrated into a single realized system. We also introduce an evaluation environment in order to measure the effect of combining various system components. Our evaluation environment employs different LL scenarios (sequences of tasks) consisting of Starcraft-2 minigames and allows for the fair, comprehensive, and quantitative comparison of different combinations of components within a challenging common evaluation environment.
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In recent years, deep learning has infiltrated every field it has touched, reducing the need for specialist knowledge and automating the process of knowledge discovery from data. This review argues that astronomy is no different, and that we are currently in the midst of a deep learning revolution that is transforming the way we do astronomy. We trace the history of astronomical connectionism from the early days of multilayer perceptrons, through the second wave of convolutional and recurrent neural networks, to the current third wave of self-supervised and unsupervised deep learning. We then predict that we will soon enter a fourth wave of astronomical connectionism, in which finetuned versions of an all-encompassing 'foundation' model will replace expertly crafted deep learning models. We argue that such a model can only be brought about through a symbiotic relationship between astronomy and connectionism, whereby astronomy provides high quality multimodal data to train the foundation model, and in turn the foundation model is used to advance astronomical research.
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我们提供了证据表明,学到的密度功能理论(``dft')的力场已准备好进行基态催化剂发现。我们的关键发现是,尽管预测的力与地面真相有很大差异,但使用从超过50 \%的评估系统中使用RPBE功能的能量与使用RPBE功能相似或较低能量的力量的力量与使用RPBE功能相似或较低的力量放松。这具有令人惊讶的含义,即学习的潜力可能已经准备好在挑战性的催化系统中替换DFT,例如在Open Catalyst 2020数据集中发现的电位。此外,我们表明,在局部谐波能量表面上具有与目标DFT能量相同的局部谐波能量表面训练的力场也能够在50 \%的情况下找到较低或相似的能量结构。与在真实能量和力量训练的标准模型相比,这种``简易电位''的收敛步骤更少,这进一步加速了计算。它的成功说明了一个关键:即使模型具有高力误差,学到的电位也可以定位能量最小值。结构优化的主要要求仅仅是学到的电位具有正确的最小值。由于学到的电位与系统大小的速度快速且尺寸为线性,因此我们的结果开辟了快速找到大型系统基础状态的可能性。
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2型糖尿病(T2DM)的早期诊断对于及时的治疗干预措施和生活方式改变至关重要。随着医学成像数据在许多患者群体中变得更广泛可用,我们试图研究是否可以在表格学习分类器模型中利用图像衍生的表型数据来预测T2DM的发病率,而无需使用侵入性血液实验室测量。我们表明,使用图像衍生表型的神经网络和决策树模型都可以预测患者T2DM状态的召回评分高达87.6%。我们还提出了与“ Syntha1c编码器”相同的结构的新颖使用,这些结构能够输出模仿血液血红蛋白A1C经验实验室测量值的可解释值。最后,我们证明了T2DM风险预测模型对输入矢量成分中小扰动的敏感性可用于预测从以前看不见的患者人群中取样的协变量的性能。
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通用数据模型解决了标准化电子健康记录(EHR)数据的许多挑战,但无法将其集成深度表型所需的资源。开放的生物学和生物医学本体论(OBO)铸造本体论提供了可用于生物学知识的语义计算表示,并能够整合多种生物医学数据。但是,将EHR数据映射到OBO Foundry本体论需要大量的手动策展和域专业知识。我们介绍了一个框架,用于将观察性医学成果合作伙伴关系(OMOP)标准词汇介绍给OBO铸造本体。使用此框架,我们制作了92,367条条件,8,615种药物成分和10,673个测量结果的映射。域专家验证了映射准确性,并且在24家医院进行检查时,映射覆盖了99%的条件和药物成分和68%的测量结果。最后,我们证明OMOP2OBO映射可以帮助系统地识别可能受益于基因检测的未诊断罕见病患者。
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当环境稀疏和非马克维亚奖励时,使用标量奖励信号的训练加强学习(RL)代理通常是不可行的。此外,在训练之前对这些奖励功能进行手工制作很容易指定,尤其是当环境的动态仅部分知道时。本文提出了一条新型的管道,用于学习非马克维亚任务规格,作为简洁的有限状态“任务自动机”,从未知环境中的代理体验情节中。我们利用两种关键算法的见解。首先,我们通过将其视为部分可观察到的MDP并为隐藏的Markov模型使用现成的算法,从而学习了由规范的自动机和环境MDP组成的产品MDP,该模型是由规范的自动机和环境MDP组成的。其次,我们提出了一种从学习的产品MDP中提取任务自动机(假定为确定性有限自动机)的新方法。我们学到的任务自动机可以使任务分解为其组成子任务,从而提高了RL代理以后可以合成最佳策略的速率。它还提供了高级环境和任务功能的可解释编码,因此人可以轻松地验证代理商是否在没有错误的情况下学习了连贯的任务。此外,我们采取步骤确保学识渊博的自动机是环境不可静止的,使其非常适合用于转移学习。最后,我们提供实验结果,以说明我们在不同环境和任务中的算法的性能及其合并先前的领域知识以促进更有效学习的能力。
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我们介绍了一种考虑复杂的环境条件,在极地地区介绍了一种在极地地区长距离海上路线计划的方法。该方法允许构建优化的路线,描述了该过程的三个主要阶段:使用不均匀网格对环境条件进行离散建模,网格最佳路径的构建以及路径平滑。为了说明不同的车辆性能,我们构建了一系列数据驱动的功能,这些功能可以应用于环境网格,以确定给定容器和网格单元的速度限制和燃料要求,以图形和地理空间表示这些数量。在描述我们的结果时,我们展示了一个示例用途,用于Polar Research船RRS David Attenborough爵士(SDA)的路线规划,核算冰的性能特征,并验证韦德尔海地区的时空路线构建,南极洲。我们通过证明路线的变化取决于季节性海冰可变性,所使用的路线规划目标函数的差异以及其他环境条件(如电流)的存在来证明这种路线构建方法的多功能性。为了证明我们的方法的普遍性,我们在北极海洋和波罗的海中介绍了例子。本手稿中概述的技术是通用的,因此可以应用于具有不同特征的血管。我们的方法不仅可以拥有一个船只计划程序,而且我们概述了该工作流程如何适用于更广泛的社区,例如商业和乘客运输。
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