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。

合奏学习结合了几个单独的模型，以获得更好的概括性能。目前，与浅层或传统模型相比，深度学习体系结构表现更好。深度合奏学习模型结合了深度学习模型以及整体学习的优势，使最终模型具有更好的概括性能。本文回顾了最先进的深度合奏模型，因此是研究人员的广泛摘要。合奏模型广泛地分类为包装，增强，堆叠，基于负相关的深度合奏模型，显式/隐式合奏，同质/异质合奏，基于决策融合策略的深层集合模型。还简要讨论了在不同领域中深层集成模型的应用。最后，我们以一些潜在的未来研究方向结束了本文。

痴呆症是一种神经精神脑障碍，通常会在一个或多个脑细胞停止部分或根本停止工作时发生。在疾病的早期阶段诊断这种疾病是从不良后果中挽救生命并为他们提供更好的医疗保健的至关重要的任务。事实证明，机器学习方法在预测疾病早期痴呆症方面是准确的。痴呆的预测在很大程度上取决于通常从归一化的全脑体积（NWBV）和地图集缩放系数（ASF）收集的收集数据类型，这些数据通常测量并从磁共振成像（MRIS）中进行校正。年龄和性别等其他生物学特征也可以帮助诊断痴呆症。尽管许多研究使用机器学习来预测痴呆症，但我们无法就这些方法的稳定性得出结论，而这些方法在不同的实验条件下更准确。因此，本文研究了有关痴呆预测的机器学习算法的性能的结论稳定性。为此，使用7种机器学习算法和两种功能还原算法，即信息增益（IG）和主成分分析（PCA）进行大量实验。为了检查这些算法的稳定性，IG的特征选择阈值从20％更改为100％，PCA尺寸从2到8。这导致了7x9 + 7x7 = 112实验。在每个实验中，都记录了各种分类评估数据。获得的结果表明，在七种算法中，支持向量机和天真的贝叶斯是最稳定的算法，同时更改选择阈值。同样，发现使用IG似乎比使用PCA预测痴呆症更有效。

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}

Label noise is an important issue in classification, with many potential negative consequences. For example, the accuracy of predictions may decrease, whereas the complexity of inferred models and the number of necessary training samples may increase. Many works in the literature have been devoted to the study of label noise and the development of techniques to deal with label noise. However, the field lacks a comprehensive survey on the different types of label noise, their consequences and the algorithms that consider label noise. This paper proposes to fill this gap. First, the definitions and sources of label noise are considered and a taxonomy of the types of label noise is proposed. Second, the potential consequences of label noise are discussed. Third, label noise-robust, label noise cleansing, and label noise-tolerant algorithms are reviewed. For each category of approaches, a short discussion is proposed to help the practitioner to choose the most suitable technique in its own particular field of application. Eventually, the design of experiments is also discussed, what may interest the researchers who would like to test their own algorithms. In this paper, label noise consists of mislabeled instances: no additional information is assumed to be available like e.g. confidences on labels.

在医疗保健系统中，需要患者使用可穿戴设备进行远程数据收集和对健康数据的实时监控以及健康状况的状态。可穿戴设备的这种采用导致收集和传输的数据量显着增加。由于设备由较小的电池电源运行，因此由于设备的高处理要求以进行数据收集和传输，因此可以快速减少它们。鉴于医疗数据的重要性，必须所有传输数据遵守严格的完整性和可用性要求。减少医疗保健数据的量和传输频率将通过使用推理算法改善设备电池寿命。有一个以准确性和效率改善传输指标的问题，彼此之间的权衡，例如提高准确性会降低效率。本文表明，机器学习可用于分析复杂的健康数据指标，例如数据传输的准确性和效率，以使用Levenberg-Marquardt算法来克服权衡问题，从而增强这两个指标，从而通过少较少的样本来传输，同时保持维护准确性。使用标准心率数据集测试该算法以比较指标。结果表明，LMA最好以3.33倍的效率进行样本数据尺寸和79.17％的精度，在7种不同的采样案例中具有相似的准确性，用于测试，但表明效率提高。与具有高效率的现有方法相比，这些提出的方法使用机器学习可以显着改善两个指标，而无需牺牲其他指标。

天然气管道中的泄漏检测是石油和天然气行业的一个重要且持续的问题。这尤其重要，因为管道是运输天然气的最常见方法。这项研究旨在研究数据驱动的智能模型使用基本操作参数检测天然气管道的小泄漏的能力，然后使用现有的性能指标比较智能模型。该项目应用观察者设计技术，使用回归分类层次模型来检测天然气管道中的泄漏，其中智能模型充当回归器，并且修改后的逻辑回归模型充当分类器。该项目使用四个星期的管道数据流研究了五个智能模型（梯度提升，决策树，随机森林，支持向量机和人工神经网络）。结果表明，虽然支持向量机和人工神经网络比其他网络更好，但由于其内部复杂性和所使用的数据量，它们并未提供最佳的泄漏检测结果。随机森林和决策树模型是最敏感的，因为它们可以在大约2小时内检测到标称流量的0.1％的泄漏。所有智能模型在测试阶段中具有高可靠性，错误警报率为零。将所有智能模型泄漏检测的平均时间与文献中的实时短暂模型进行了比较。结果表明，智能模型在泄漏检测问题中的表现相对较好。该结果表明，可以与实时瞬态模型一起使用智能模型，以显着改善泄漏检测结果。

Machine Learning (ML) software has been widely adopted in modern society, with reported fairness implications for minority groups based on race, sex, age, etc. Many recent works have proposed methods to measure and mitigate algorithmic bias in ML models. The existing approaches focus on single classifier-based ML models. However, real-world ML models are often composed of multiple independent or dependent learners in an ensemble (e.g., Random Forest), where the fairness composes in a non-trivial way. How does fairness compose in ensembles? What are the fairness impacts of the learners on the ultimate fairness of the ensemble? Can fair learners result in an unfair ensemble? Furthermore, studies have shown that hyperparameters influence the fairness of ML models. Ensemble hyperparameters are more complex since they affect how learners are combined in different categories of ensembles. Understanding the impact of ensemble hyperparameters on fairness will help programmers design fair ensembles. Today, we do not understand these fully for different ensemble algorithms. In this paper, we comprehensively study popular real-world ensembles: bagging, boosting, stacking and voting. We have developed a benchmark of 168 ensemble models collected from Kaggle on four popular fairness datasets. We use existing fairness metrics to understand the composition of fairness. Our results show that ensembles can be designed to be fairer without using mitigation techniques. We also identify the interplay between fairness composition and data characteristics to guide fair ensemble design. Finally, our benchmark can be leveraged for further research on fair ensembles. To the best of our knowledge, this is one of the first and largest studies on fairness composition in ensembles yet presented in the literature.

在全球范围内，有实质性的未满足需要有效地诊断各种疾病。不同疾病机制的复杂性和患者人群的潜在症状具有巨大挑战，以发展早期诊断工具和有效治疗。机器学习（ML），人工智能（AI）区域，使研究人员，医师和患者能够解决这些问题的一些问题。基于相关研究，本综述解释了如何使用机器学习（ML）和深度学习（DL）来帮助早期识别许多疾病。首先，使用来自Scopus和Science（WOS）数据库的数据来给予所述出版物的生物计量研究。对1216个出版物的生物计量研究进行了确定，以确定最多产的作者，国家，组织和最引用的文章。此次审查总结了基于机器学习的疾病诊断（MLBDD）的最新趋势和方法，考虑到以下因素：算法，疾病类型，数据类型，应用和评估指标。最后，该文件突出了关键结果，并向未来的未来趋势和机遇提供了解。

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。

2019年12月底，首先在武汉中国首次确定了新型冠状病毒（SARS-COV-2）和所得疾病Covid-19。该疾病通过遏制措施滑落，其中一个已知的案例在美国在2020年1月20日被确定。在本文中，我们利用来自大学间财团的调查数据进行政治和社会研究，并应用几种统计和机器学习模型和技术，如决策树，多项式物流回归，天真贝叶斯，k-intele邻居，支持向量机，神经网络，随机森林，梯度树提升，Xgboost，Catboost，LightGBM，合成少数群体过采样和Chi-Squared测试分析Covid-19大流行对美国前线工人心理健康的影响。通过对适用于心理健康调查数据的许多模型的解释，我们已经得出结论，预测前线工人心理健康衰退的最重要因素是个人所在的医疗保健角色（护士，急诊室工作人员，外科医生， ），其次是个人在上周睡眠量，Covid-19相关新闻的数量在一天，工人的年龄和酒精和大麻的使用量平均消耗。

近年来，随着传感器和智能设备的广泛传播，物联网（IoT）系统的数据生成速度已大大增加。在物联网系统中，必须经常处理，转换和分析大量数据，以实现各种物联网服务和功能。机器学习（ML）方法已显示出其物联网数据分析的能力。但是，将ML模型应用于物联网数据分析任务仍然面临许多困难和挑战，特别是有效的模型选择，设计/调整和更新，这给经验丰富的数据科学家带来了巨大的需求。此外，物联网数据的动态性质可能引入概念漂移问题，从而导致模型性能降解。为了减少人类的努力，自动化机器学习（AUTOML）已成为一个流行的领域，旨在自动选择，构建，调整和更新机器学习模型，以在指定任务上实现最佳性能。在本文中，我们对Automl区域中模型选择，调整和更新过程中的现有方法进行了审查，以识别和总结将ML算法应用于IoT数据分析的每个步骤的最佳解决方案。为了证明我们的发现并帮助工业用户和研究人员更好地实施汽车方法，在这项工作中提出了将汽车应用于IoT异常检测问题的案例研究。最后，我们讨论并分类了该领域的挑战和研究方向。

Concept drift describes unforeseeable changes in the underlying distribution of streaming data over time. Concept drift research involves the development of methodologies and techniques for drift detection, understanding and adaptation. Data analysis has revealed that machine learning in a concept drift environment will result in poor learning results if the drift is not addressed. To help researchers identify which research topics are significant and how to apply related techniques in data analysis tasks, it is necessary that a high quality, instructive review of current research developments and trends in the concept drift field is conducted. In addition, due to the rapid development of concept drift in recent years, the methodologies of learning under concept drift have become noticeably systematic, unveiling a framework which has not been mentioned in literature. This paper reviews over 130 high quality publications in concept drift related research areas, analyzes up-to-date developments in methodologies and techniques, and establishes a framework of learning under concept drift including three main components: concept drift detection, concept drift understanding, and concept drift adaptation. This paper lists and discusses 10 popular synthetic datasets and 14 publicly available benchmark datasets used for evaluating the performance of learning algorithms aiming at handling concept drift. Also, concept drift related research directions are covered and discussed. By providing state-of-the-art knowledge, this survey will directly support researchers in their understanding of research developments in the field of learning under concept drift.

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.

In the last years many accurate decision support systems have been constructed as black boxes, that is as systems that hide their internal logic to the user. This lack of explanation constitutes both a practical and an ethical issue. The literature reports many approaches aimed at overcoming this crucial weakness sometimes at the cost of scarifying accuracy for interpretability. The applications in which black box decision systems can be used are various, and each approach is typically developed to provide a solution for a specific problem and, as a consequence, delineating explicitly or implicitly its own definition of interpretability and explanation. The aim of this paper is to provide a classification of the main problems addressed in the literature with respect to the notion of explanation and the type of black box system. Given a problem definition, a black box type, and a desired explanation this survey should help the researcher to find the proposals more useful for his own work. The proposed classification of approaches to open black box models should also be useful for putting the many research open questions in perspective.

Concept drift primarily refers to an online supervised learning scenario when the relation between the input data and the target variable changes over time. Assuming a general knowledge of supervised learning in this paper we characterize adaptive learning process, categorize existing strategies for handling concept drift, overview the most representative, distinct and popular techniques and algorithms, discuss evaluation methodology of adaptive algorithms, and present a set of illustrative applications. The survey covers the different facets of concept drift in an integrated way to reflect on the existing scattered state-of-the-art. Thus, it aims at providing a comprehensive introduction to the concept drift adaptation for researchers, industry analysts and practitioners.

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.

随着网络攻击和网络间谍活动的增长，如今需要更好，更强大的入侵检测系统（IDS）的需求更加有必要。 ID的基本任务是在检测Internet的攻击方面充当第一道防线。随着入侵者的入侵策略变得越来越复杂且难以检测，研究人员已经开始应用新颖的机器学习（ML）技术来有效地检测入侵者，从而保留互联网用户对整个互联网网络安全的信息和整体信任。在过去的十年中，基于ML和深度学习（DL）架构的侵入检测技术的爆炸激增，这些架构在各种基于网络安全的数据集上，例如DARPA，KDDCUP'99，NSL-KDD，CAIDA，CAIDA，CTU--- 13，UNSW-NB15。在这项研究中，我们回顾了当代文献，并提供了对不同类型的入侵检测技术的全面调查，该技术将支持向量机（SVMS）算法作为分类器。我们仅专注于在网络安全中对两个最广泛使用的数据集进行评估的研究，即KDDCUP'99和NSL-KDD数据集。我们提供了每种方法的摘要，确定了SVMS分类器的作用以及研究中涉及的所有其他算法。此外，我们以表格形式对每种方法进行了批判性综述，突出了所调查的每种方法的性能指标，优势和局限性。

无论是在功能选择的领域还是可解释的AI领域，都有基于其重要性的“排名”功能的愿望。然后可以将这种功能重要的排名用于：（1）减少数据集大小或（2）解释机器学习模型。但是，在文献中，这种特征排名没有以系统的，一致的方式评估。许多论文都有不同的方式来争论哪些具有重要性排名最佳的特征。本文通过提出一种新的评估方法来填补这一空白。通过使用合成数据集，可以事先知道特征重要性得分，从而可以进行更系统的评估。为了促进使用新方法的大规模实验，在Python建造了一个名为FSEVAL的基准测定框架。该框架允许并行运行实验，并在HPC系统上的计算机上分布。通过与名为“权重和偏见”的在线平台集成，可以在实时仪表板上进行交互探索图表。该软件作为开源软件发布，并在PYPI平台上以包裹发行。该研究结束时，探索了一个这样的大规模实验，以在许多方面找到参与算法的优势和劣势。

在这个时代，作为医疗的主要重点，这一时刻已经到来了。尽管令人印象深刻，但已经开发出来检测疾病的多种技术。此时，有一些类型的疾病COVID-19，正常烟，偏头痛，肺病，心脏病，肾脏疾病，糖尿病，胃病，胃病，胃病，骨骼疾病，自闭症是非常常见的疾病。在此分析中，我们根据疾病的症状进行了分析疾病症状的预测。我们研究了一系列症状，并接受了人们的调查以完成任务。已经采用了几种分类算法来训练模型。此外，使用性能评估矩阵来衡量模型的性能。最后，我们发现零件分类器超过了其他分类器。