Human behavior emerges from planning over elaborate decompositions of tasks into goals, subgoals, and low-level actions. How are these decompositions created and used? Here, we propose and evaluate a normative framework for task decomposition based on the simple idea that people decompose tasks to reduce the overall cost of planning while maintaining task performance. Analyzing 11,117 distinct graph-structured planning tasks, we find that our framework justifies several existing heuristics for task decomposition and makes predictions that can be distinguished from two alternative normative accounts. We report a behavioral study of task decomposition ($N=806$) that uses 30 randomly sampled graphs, a larger and more diverse set than that of any previous behavioral study on this topic. We find that human responses are more consistent with our framework for task decomposition than alternative normative accounts and are most consistent with a heuristic -- betweenness centrality -- that is justified by our approach. Taken together, our results provide new theoretical insight into the computational principles underlying the intelligent structuring of goal-directed behavior.

获得抽象知识的能力是人类智力的标志，许多人认为是人类和神经网络模型之间的核心差异之一。代理可以通过元学习对抽象的归纳偏见，在那里他们接受了共享可以学习和应用的一些抽象结构的任务分布的培训。但是，由于很难解释神经网络，因此很难判断代理人是学会了潜在的抽象，或者是该抽象特征的统计模式。在这项工作中，我们比较了人类和代理在荟萃方面学习范式中的表现，其中从抽象规则中产生了任务。我们定义了一种用于构建“任务Metamers”的新方法，该方法与抽象任务的统计数据非常匹配，但使用了不同的基本生成过程，并评估了在抽象和Metamer任务上的性能。在我们的第一组实验中，我们发现人类在抽象任务上的表现要比MetAmer任务更好，而广泛使用的元强化学习代理在抽象任务上的表现要比匹配的Metamers差。在第二组实验中，我们将任务基于直接从经验鉴定的人类先验得出的抽象基础。我们利用相同的过程来生成相应的METAMER任务，并看到人与代理之间的相同双重分离。这项工作为表征人类和机器学习之间的差异奠定了基础，可以在未来的工作中用于以人类行为开发机器。

Network intrusion detection systems (NIDS) to detect malicious attacks continues to meet challenges. NIDS are vulnerable to auto-generated port scan infiltration attempts and NIDS are often developed offline, resulting in a time lag to prevent the spread of infiltration to other parts of a network. To address these challenges, we use hypergraphs to capture evolving patterns of port scan attacks via the set of internet protocol addresses and destination ports, thereby deriving a set of hypergraph-based metrics to train a robust and resilient ensemble machine learning (ML) NIDS that effectively monitors and detects port scanning activities and adversarial intrusions while evolving intelligently in real-time. Through the combination of (1) intrusion examples, (2) NIDS update rules, (3) attack threshold choices to trigger NIDS retraining requests, and (4) production environment with no prior knowledge of the nature of network traffic 40 scenarios were auto-generated to evaluate the ML ensemble NIDS comprising three tree-based models. Results show that under the model settings of an Update-ALL-NIDS rule (namely, retrain and update all the three models upon the same NIDS retraining request) the proposed ML ensemble NIDS produced the best results with nearly 100% detection performance throughout the simulation, exhibiting robustness in the complex dynamics of the simulated cyber-security scenario.

Stock and flow diagrams are already an important tool in epidemiology, but category theory lets us go further and treat these diagrams as mathematical entities in their own right. In this chapter we use communicable disease models created with our software, StockFlow.jl, to explain the benefits of the categorical approach. We first explain the category of stock-flow diagrams, and note the clear separation between the syntax of these diagrams and their semantics, demonstrating three examples of semantics already implemented in the software: ODEs, causal loop diagrams, and system structure diagrams. We then turn to two methods for building large stock-flow diagrams from smaller ones in a modular fashion: composition and stratification. Finally, we introduce the open-source ModelCollab software for diagram-based collaborative modeling. The graphical user interface of this web-based software lets modelers take advantage of the ideas discussed here without any knowledge of their categorical foundations.

开发有效的自动分类器将真实来源与工件分开，对于宽场光学调查的瞬时随访至关重要。在图像差异过程之后，从减法伪像的瞬态检测鉴定是此类分类器的关键步骤，称为真实 - 博格斯分类问题。我们将自我监督的机器学习模型，深入的自组织地图（DESOM）应用于这个“真实的模拟”分类问题。 DESOM结合了自动编码器和一个自组织图以执行聚类，以根据其维度降低的表示形式来区分真实和虚假的检测。我们使用32x32归一化检测缩略图作为底部的输入。我们展示了不同的模型训练方法，并发现我们的最佳DESOM分类器显示出6.6％的检测率，假阳性率为1.5％。 Desom提供了一种更细微的方法来微调决策边界，以确定与其他类型的分类器（例如在神经网络或决策树上构建的）结合使用时可能进行的实际检测。我们还讨论了DESOM及其局限性的其他潜在用法。

网络脆弱性管理是网络安全操作中心（CSOC）的关键功能，该中心有助于保护组织免受计算机和网络系统上的网络攻击。对手比CSOC拥有不对称的优势，因为这些系统中的缺陷次数与安全团队的扩展率相比，在资源受限的环境中减轻它们的速度相比，其速度明显更高。当前的方法是确定性和一次性决策方法，在优先考虑和选择缓解漏洞时，这些方法不考虑未来的不确定性。这些方法还受到资源的亚最佳分布的约束，没有灵活性来调整其对脆弱性到达波动的响应的灵活性。我们提出了一个新颖的框架，深深的瓦尔曼，由深入的强化学习代理和整数编程方法组成，以填补网络脆弱性管理过程中的这一空白。我们的顺序决策框架首先确定在给定系统状态下不确定性下为缓解的近乎最佳的资源，然后确定最佳的缓解优先级漏洞实例。我们提出的框架优于当前方法在一年内观察到的模拟和现实世界脆弱性数据优先选择重要的组织特定漏洞。

互联的战地信息共享设备的扩散，称为战场互联网（Iobt），介绍了几个安全挑战。 Iobt运营环境所固有的是对抗机器学习的实践，试图规避机器学习模型。这项工作探讨了在网络入侵检测系统设置中对异常检测的成本效益无监督学习和基于图形的方法的可行性，并利用了集合方法来监督异常检测问题的学习。我们在培训监督模型时纳入了一个现实的对抗性培训机制，以实现对抗性环境的强大分类性能。结果表明，无监督和基于图形的方法在通过两个级别的监督堆叠集合方法检测异常（恶意活动）时表现优于检测异常（恶意活动）。该模型由第一级别的三个不同的分类器组成，然后是第二级的天真贝叶斯或决策树分类器。对于所有测试水平的两个分类器，该模型将在0.97高于0.97以上的F1分数。值得注意的是，天真贝叶斯是最快的两个分类器平均1.12秒，而决策树保持最高的AUC评分为0.98。

In this paper, we propose a novel technique, namely INVALIDATOR, to automatically assess the correctness of APR-generated patches via semantic and syntactic reasoning. INVALIDATOR reasons about program semantic via program invariants while it also captures program syntax via language semantic learned from large code corpus using the pre-trained language model. Given a buggy program and the developer-patched program, INVALIDATOR infers likely invariants on both programs. Then, INVALIDATOR determines that a APR-generated patch overfits if: (1) it violates correct specifications or (2) maintains errors behaviors of the original buggy program. In case our approach fails to determine an overfitting patch based on invariants, INVALIDATOR utilizes a trained model from labeled patches to assess patch correctness based on program syntax. The benefit of INVALIDATOR is three-fold. First, INVALIDATOR is able to leverage both semantic and syntactic reasoning to enhance its discriminant capability. Second, INVALIDATOR does not require new test cases to be generated but instead only relies on the current test suite and uses invariant inference to generalize the behaviors of a program. Third, INVALIDATOR is fully automated. We have conducted our experiments on a dataset of 885 patches generated on real-world programs in Defects4J. Experiment results show that INVALIDATOR correctly classified 79% overfitting patches, accounting for 23% more overfitting patches being detected by the best baseline. INVALIDATOR also substantially outperforms the best baselines by 14% and 19% in terms of Accuracy and F-Measure, respectively.

When robots learn reward functions using high capacity models that take raw state directly as input, they need to both learn a representation for what matters in the task -- the task ``features" -- as well as how to combine these features into a single objective. If they try to do both at once from input designed to teach the full reward function, it is easy to end up with a representation that contains spurious correlations in the data, which fails to generalize to new settings. Instead, our ultimate goal is to enable robots to identify and isolate the causal features that people actually care about and use when they represent states and behavior. Our idea is that we can tune into this representation by asking users what behaviors they consider similar: behaviors will be similar if the features that matter are similar, even if low-level behavior is different; conversely, behaviors will be different if even one of the features that matter differs. This, in turn, is what enables the robot to disambiguate between what needs to go into the representation versus what is spurious, as well as what aspects of behavior can be compressed together versus not. The notion of learning representations based on similarity has a nice parallel in contrastive learning, a self-supervised representation learning technique that maps visually similar data points to similar embeddings, where similarity is defined by a designer through data augmentation heuristics. By contrast, in order to learn the representations that people use, so we can learn their preferences and objectives, we use their definition of similarity. In simulation as well as in a user study, we show that learning through such similarity queries leads to representations that, while far from perfect, are indeed more generalizable than self-supervised and task-input alternatives.

The latent space of autoencoders has been improved for clustering image data by jointly learning a t-distributed embedding with a clustering algorithm inspired by the neighborhood embedding concept proposed for data visualization. However, multivariate tabular data pose different challenges in representation learning than image data, where traditional machine learning is often superior to deep tabular data learning. In this paper, we address the challenges of learning tabular data in contrast to image data and present a novel Gaussian Cluster Embedding in Autoencoder Latent Space (G-CEALS) algorithm by replacing t-distributions with multivariate Gaussian clusters. Unlike current methods, the proposed approach independently defines the Gaussian embedding and the target cluster distribution to accommodate any clustering algorithm in representation learning. A trained G-CEALS model extracts a quality embedding for unseen test data. Based on the embedding clustering accuracy, the average rank of the proposed G-CEALS method is 1.4 (0.7), which is superior to all eight baseline clustering and cluster embedding methods on seven tabular data sets. This paper shows one of the first algorithms to jointly learn embedding and clustering to improve multivariate tabular data representation in downstream clustering.