在运输系统中引入信息和通信技术(ICT)导致了几个优势(运输,移动性,交通管理)。然而,它可能在增加安全挑战方面带来一些缺点,也与人类行为有关。作为一个例子,在过去的几十年中,尝试表征驱动程序的行为大多是针对性的。本文提出了一种安全的例程,一种范式,它使用驾驶员习惯来探讨驱动程序识别,特别是将车辆的所有者与其他驱动程序区分开来。我们根据机器学习技术与其他三项现有研究工作相结合评估安全的例程。结果是使用众所周知的指标来测量的,并显示安全的常规优于比较的作品。
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The costs and impacts of government corruption range from impairing a country's economic growth to affecting its citizens' well-being and safety. Public contracting between government dependencies and private sector instances, referred to as public procurement, is a fertile land of opportunity for corrupt practices, generating substantial monetary losses worldwide. Thus, identifying and deterring corrupt activities between the government and the private sector is paramount. However, due to several factors, corruption in public procurement is challenging to identify and track, leading to corrupt practices going unnoticed. This paper proposes a machine learning model based on an ensemble of random forest classifiers, which we call hyper-forest, to identify and predict corrupt contracts in M\'exico's public procurement data. This method's results correctly detect most of the corrupt and non-corrupt contracts evaluated in the dataset. Furthermore, we found that the most critical predictors considered in the model are those related to the relationship between buyers and suppliers rather than those related to features of individual contracts. Also, the method proposed here is general enough to be trained with data from other countries. Overall, our work presents a tool that can help in the decision-making process to identify, predict and analyze corruption in public procurement contracts.
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The cyber-physical convergence is opening up new business opportunities for industrial operators. The need for deep integration of the cyber and the physical worlds establishes a rich business agenda towards consolidating new system and network engineering approaches. This revolution would not be possible without the rich and heterogeneous sources of data, as well as the ability of their intelligent exploitation, mainly due to the fact that data will serve as a fundamental resource to promote Industry 4.0. One of the most fruitful research and practice areas emerging from this data-rich, cyber-physical, smart factory environment is the data-driven process monitoring field, which applies machine learning methodologies to enable predictive maintenance applications. In this paper, we examine popular time series forecasting techniques as well as supervised machine learning algorithms in the applied context of Industry 4.0, by transforming and preprocessing the historical industrial dataset of a packing machine's operational state recordings (real data coming from the production line of a manufacturing plant from the food and beverage domain). In our methodology, we use only a single signal concerning the machine's operational status to make our predictions, without considering other operational variables or fault and warning signals, hence its characterization as ``agnostic''. In this respect, the results demonstrate that the adopted methods achieve a quite promising performance on three targeted use cases.
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Network intrusion detection systems (NIDSs) play an important role in computer network security. There are several detection mechanisms where anomaly-based automated detection outperforms others significantly. Amid the sophistication and growing number of attacks, dealing with large amounts of data is a recognized issue in the development of anomaly-based NIDS. However, do current models meet the needs of today's networks in terms of required accuracy and dependability? In this research, we propose a new hybrid model that combines machine learning and deep learning to increase detection rates while securing dependability. Our proposed method ensures efficient pre-processing by combining SMOTE for data balancing and XGBoost for feature selection. We compared our developed method to various machine learning and deep learning algorithms to find a more efficient algorithm to implement in the pipeline. Furthermore, we chose the most effective model for network intrusion based on a set of benchmarked performance analysis criteria. Our method produces excellent results when tested on two datasets, KDDCUP'99 and CIC-MalMem-2022, with an accuracy of 99.99% and 100% for KDDCUP'99 and CIC-MalMem-2022, respectively, and no overfitting or Type-1 and Type-2 issues.
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装袋和升压是在机器学习(ml)中的两个流行的集合方法,产生许多单独的决策树。由于这些方法的固有组合特性,它们通常以预测性能更优于单决定树或其他ML模型。然而,为每个决策树生成许多决定路径,增加了模型的整体复杂性,并阻碍了其在需要值得信赖和可解释的决策的域中的域,例如金融,社会护理和保健。因此,随着决策的数量升高,袋装和升降算法(例如随机森林和自适应升压)的解释性降低。在本文中,我们提出了一种视觉分析工具,该工具旨在帮助用户通过彻底的视觉检查工作流程从这种ML模型中提取决策,包括选择一套鲁棒和不同的模型(源自不同的集合学习算法),选择重要的功能根据他们的全球贡献,决定哪些决定对于全球解释(或本地,具体案件)是必不可少的。结果是基于多个模型的协议和用户出口的探索手动决策的最终决定。最后,我们通过用例,使用场景和用户学习评估患者的适用性和有效性。
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关键基础设施(CI)的安全和安全问题正在增长,因为攻击者越来越多地采用无人机作为敏感领空中的攻击矢量,例如机场,军事基地,城市中心和拥挤的地方。由于违法行为和限制空域的入侵,无人机的迅速扩散,用于商品,运输娱乐活动和其他商业应用程序引起了CI操作员的严重关注。在这种情况下,需要一个具有成本效益的框架来检测,分类和确定无人机的存在。在本文中,我们证明了CI操作员可以使用名为Uranus的廉价基于RF的检测框架来检测,分类和识别及时有效的无人机区域的无人机区域。我们的实验表明,通过使用随机森林分类器,我们在一个或多个特定的无人机的分类中达到了93.4%的分类精度。跟踪性能的平均值= 0.3650,MSE = 0.9254和R2 = 0.7502,其准确度达到了精度。我们的框架已被发布为开源,以使社区能够验证我们的发现,并将天王星作为现成的基础进行进一步分析。
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Reliable and robust user identification and authentication are important and often necessary requirements for many digital services. It becomes paramount in social virtual reality (VR) to ensure trust, specifically in digital encounters with lifelike realistic-looking avatars as faithful replications of real persons. Recent research has shown that the movements of users in extended reality (XR) systems carry user-specific information and can thus be used to verify their identities. This article compares three different potential encodings of the motion data from head and hands (scene-relative, body-relative, and body-relative velocities), and the performances of five different machine learning architectures (random forest, multi-layer perceptron, fully recurrent neural network, long-short term memory, gated recurrent unit). We use the publicly available dataset "Talking with Hands" and publish all code to allow reproducibility and to provide baselines for future work. After hyperparameter optimization, the combination of a long-short term memory architecture and body-relative data outperformed competing combinations: the model correctly identifies any of the 34 subjects with an accuracy of 100% within 150 seconds. Altogether, our approach provides an effective foundation for behaviometric-based identification and authentication to guide researchers and practitioners. Data and code are published under https://go.uniwue.de/58w1r.
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Building an accurate model of travel behaviour based on individuals' characteristics and built environment attributes is of importance for policy-making and transportation planning. Recent experiments with big data and Machine Learning (ML) algorithms toward a better travel behaviour analysis have mainly overlooked socially disadvantaged groups. Accordingly, in this study, we explore the travel behaviour responses of low-income individuals to transit investments in the Greater Toronto and Hamilton Area, Canada, using statistical and ML models. We first investigate how the model choice affects the prediction of transit use by the low-income group. This step includes comparing the predictive performance of traditional and ML algorithms and then evaluating a transit investment policy by contrasting the predicted activities and the spatial distribution of transit trips generated by vulnerable households after improving accessibility. We also empirically investigate the proposed transit investment by each algorithm and compare it with the city of Brampton's future transportation plan. While, unsurprisingly, the ML algorithms outperform classical models, there are still doubts about using them due to interpretability concerns. Hence, we adopt recent local and global model-agnostic interpretation tools to interpret how the model arrives at its predictions. Our findings reveal the great potential of ML algorithms for enhanced travel behaviour predictions for low-income strata without considerably sacrificing interpretability.
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越来越多的工作已经认识到利用机器学习(ML)进步的重要性,以满足提取访问控制属性,策略挖掘,策略验证,访问决策等有效自动化的需求。在这项工作中,我们调查和总结了各种ML解决不同访问控制问题的方法。我们提出了ML模型在访问控制域中应用的新分类学。我们重点介绍当前的局限性和公开挑战,例如缺乏公共现实世界数据集,基于ML的访问控制系统的管理,了解黑盒ML模型的决策等,并列举未来的研究方向。
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机器学习(ML)应用程序的数据量不断增长。不仅是观察的数量,特别是测量变量的数量(特征)增加了持续的数字化。选择最适合预测建模的功能是ML在商业和研究中取得成功的重要杠杆。特征选择方法(FSM)独立于某种ML算法 - 所谓的过滤方法 - 已毫无意义地建议,但研究人员和定量建模的指导很少,以选择典型ML问题的适当方法。本次审查在特征选择基准上综合了大量文献,并评估了58种方法在广泛使用的R环境中的性能。对于具体的指导,我们考虑了四种典型的数据集方案,这些情况挑战ML模型(嘈杂,冗余,不平衡数据和具有比观察特征更多的案例)。绘制早期基准的经验,该基准测试较少的FSMS,我们根据四个标准进行比较方法的性能(预测性能,所选的相关功能数,功能集和运行时的稳定性)。我们发现依赖于随机森林方法的方法,双输入对称相关滤波器(浪费)和联合杂质滤波器(Jim)是给定的数据集方案的良好性候选方法。
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分类器的合奏结合了几个单个分类器,以提供最终的预测或分类决策。一个越来越令人发指的问题是,此类系统是否可以胜过单个最佳分类器。如果是这样,哪种形式的分类器合奏(也称为多个分类器学习系统或多个分类器)在合奏本身的规模或多样性中产生最重要的好处?鉴于用于检测自闭症特征的测试是耗时且昂贵的,因此开发了一种将提供最佳结果和测量自闭症谱系障碍(ASD)的系统。在本文中,评估了几个单一和后来的多个分类器学习系统,以预测和确定影响或有助于ASD的因素出于早期筛查目的的能力。行为数据和机器人增强疗法的3,000次课程和300小时的数据集,该疗法被记录为61名儿童。仿真结果表明,与单个分类器相比,多个分类器学习系统(尤其是每个集合具有三个分类器的人)的优越预测性能,可以通过装袋和增强获得出色的结果。看来,社会交流手势仍然是儿童ASD问题的关键因素。
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机器学习(ML)生命周期涉及一系列迭代步骤,从有效的收集和准备数据,包括复杂的特征工程流程,对结果的演示和改进,各种步骤中的各种算法选择。特征工程尤其可以对ML非常有益,导致许多改进,例如提高预测结果,降低计算时间,减少过度噪音,并提高培训期间所采取的决策背后的透明度。尽管如此,虽然存在多个视觉分析工具来监控和控制ML生命周期的不同阶段(特别是与数据和算法相关的阶段),但功能工程支持仍然不足。在本文中,我们提出了FightEnvi,一种专门设计用于协助特征工程过程的视觉分析系统。我们建议的系统可帮助用户选择最重要的功能,将原始功能转换为强大的替代方案,并进行不同的特征生成组合。此外,数据空间切片允许用户探索本地和全局尺度上的功能的影响。 Feationenvi利用多种自动特征选择技术;此外,它目视指导用户有统计证据的关于每个特征的影响(或功能的子集)。最终结果是通过多种验证度量评估的重新设计的重新设计特征。用两种用例和案例研究证明了FeatureenVI的有用性和适用性。我们还向评估我们系统的有效性以及评估我们系统的有效性的观众报告反馈。
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Dataset scaling, also known as normalization, is an essential preprocessing step in a machine learning pipeline. It is aimed at adjusting attributes scales in a way that they all vary within the same range. This transformation is known to improve the performance of classification models, but there are several scaling techniques to choose from, and this choice is not generally done carefully. In this paper, we execute a broad experiment comparing the impact of 5 scaling techniques on the performances of 20 classification algorithms among monolithic and ensemble models, applying them to 82 publicly available datasets with varying imbalance ratios. Results show that the choice of scaling technique matters for classification performance, and the performance difference between the best and the worst scaling technique is relevant and statistically significant in most cases. They also indicate that choosing an inadequate technique can be more detrimental to classification performance than not scaling the data at all. We also show how the performance variation of an ensemble model, considering different scaling techniques, tends to be dictated by that of its base model. Finally, we discuss the relationship between a model's sensitivity to the choice of scaling technique and its performance and provide insights into its applicability on different model deployment scenarios. Full results and source code for the experiments in this paper are available in a GitHub repository.\footnote{https://github.com/amorimlb/scaling\_matters}
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分类链是一种用于在多标签分类中建模标签依赖性的有效技术。但是,该方法需要标签的固定静态顺序。虽然理论上,任何顺序都足够了,实际上,该订单对最终预测的质量具有大量影响。动态分类链表示每个实例对分类的想法,可以动态选择预测标签的顺序。这种方法的天真实现的复杂性是禁止的,因为它需要训练一系列分类器,以满足标签的每种可能置换。为了有效地解决这个问题,我们提出了一种基于随机决策树的新方法,该方法可以动态地选择每个预测的标签排序。我们凭经验展示了下一个标签的动态选择,通过在否则不变的随机决策树模型下使用静态排序。 %和实验环境。此外,我们还展示了基于极端梯度提升树的替代方法,其允许更具目标的动态分级链训练。我们的结果表明,该变体优于随机决策树和其他基于树的多标签分类方法。更重要的是,动态选择策略允许大大加速培训和预测。
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高等教育机构年度排名(HEIS)是一种全球性现象,对高等教育景观产生重大影响。大多数赫斯密切关注排名结果,并期待提高他们的行列。但是,保持良好的等级和在排名中的上升是一项艰巨的任务,因为它需要相当大的资源,努力和性能改进计划。在这项工作中,首先,我们展示了利用相关性热手套的探索性数据分析(EDA),盒子图可以帮助理解排名数据的广泛趋势。随后,我们介绍了使用基于决策树(DT)的算法对排名数据进行分类的新颖思想,并使用数据可视化技术检索级别改进的决策路径。使用LAPLACE校正到概率估计,我们量化了从可解释的DT模型获得的不同决策路径附带的确定性。拟议的方法可以援助大学和希斯定量评估改进的范围,拟定了一个细粒度的长期行动计划,并准备了合适的路线图。
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决策树学习是机器学习中广泛使用的方法,在需要简洁明了的模型的应用中受到青睐。传统上,启发式方法用于快速生产具有相当高准确性的模型。然而,一个普遍的批评是,从精度和大小方面,所产生的树可能不一定是数据的最佳表示。近年来,这激发了最佳分类树算法的发展,这些算法与执行一系列本地最佳决策的启发式方法相比,在全球范围内优化决策树。我们遵循这一工作线,并提供了一种基于动态编程和搜索的最佳分类树的新颖算法。我们的算法支持对树的深度和节点数量的约束。我们方法的成功归因于一系列专门技术,这些技术利用了分类树独有的属性。传统上,最佳分类树的算法受到了高运行时的困扰和有限的可伸缩性,但我们在一项详细的实验研究中表明,我们的方法仅使用最先进的时间所需的时间,并且可以处理数十个数据集的数据集在数千个实例中,提供了几个数量级的改进,并特别有助于实现最佳决策树的实现。
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基于机器学习(ML)的系统的制作需要在其生命周期中进行统计控制。仔细量化业务需求和识别影响业务需求的关键因素降低了项目故障的风险。业务需求的量化导致随机变量的定义,表示通过统计实验需要分析的系统关键性能指标。此外,可提供的培训和实验结果产生影响系统的设计。开发系统后,测试并不断监控,以确保其符合其业务需求。这是通过持续应用统计实验来分析和控制关键绩效指标来完成的。本书教授制作和开发基于ML的系统的艺术。它倡导“首先”方法,强调从项目生命周期开始定义统计实验的需要。它还详细讨论了如何在整个生命周期中对基于ML的系统进行统计控制。
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这项工作提供了可靠的nids(R-nids),一种新的机器学习方法(ML)的网络入侵检测系统(NIDS),允许ML模型在集成数据集上工作,从不同数据集中具有不同信息的学习过程。因此,R-NIDS针对更强大的模型的设计,比传统方法更好地概括。我们还提出了一个名为UNK21的新数据集。它是由三个最着名的网络数据集(UGR'16,USNW-NB15和NLS-KDD)构建,每个网络环境收集,使用不同的特征和类,通过使用数据聚合方法R-nids。在r-nids之后,在这项工作中,我们建议基于文献中的三个最常见的数据集的信息来构建两个着名的ML模型(一个线性和非线性的一个),用于NIDS评估中的三个,集成在UNK21中的那些。所提出的方法优惠展示了作为NIDS解决方案训练的两种ML模型的结果可以从这种方法中受益,在新提议的UNK21数据集上培训时能够更好地概括。此外,这些结果用统计工具仔细分析了对我们的结论提供了高度信心的统计工具。
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在整个宇宙学模拟中,初始条件中的物质密度场的性质对今天形成的结构的特征具有决定性的影响。在本文中,我们使用随机森林分类算法来推断暗物质颗粒是否追溯到初始条件,最终将在肿块上高于一些阈值的暗物质卤素。该问题可能被构成为二进制分类任务,其中物质密度字段的初始条件映射到由光环发现者程序提供的分类标签。我们的研究结果表明,随机森林是有效的工具,无法在不运行完整过程的情况下预测宇宙学模拟的输出。在将来可能使用这些技术来降低计算时间并更有效地探索不同暗物质/暗能候选对宇宙结构的形成的影响。
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人们的个人卫生习惯在每日生活方式中照顾身体和健康的状况。保持良好的卫生习惯不仅减少了患疾病的机会,而且还可以降低社区中传播疾病的风险。鉴于目前的大流行,每天的习惯,例如洗手或定期淋浴,在人们中至关重要,尤其是对于单独生活在家里或辅助生活设施中的老年人。本文提出了一个新颖的非侵入性框架,用于使用我们采用机器学习技术的振动传感器监测人卫生。该方法基于地球通传感器,数字化器和实用外壳中具有成本效益的计算机板的组合。监测日常卫生常规可能有助于医疗保健专业人员积极主动,而不是反应性,以识别和控制社区内潜在暴发的传播。实验结果表明,将支持向量机(SVM)用于二元分类,在不同卫生习惯的分类中表现出约95%的有希望的准确性。此外,基于树的分类器(随机福雷斯特和决策树)通过实现最高精度(100%)优于其他模型,这意味着可以使用振动和非侵入性传感器对卫生事件进行分类,以监测卫生活动。
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