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Early identification of scientific breakthroughs through outlier analysis based on research entities
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作者 Yang Zhao Mengting Zhang +1 位作者 Xiaoli Chen Zhixiong Zhang 《Journal of Data and Information Science》 CSCD 2024年第4期90-109,共20页
Purpose:To address the“anomalies”that occur when scientific breakthroughs emerge,this study focuses on identifying early signs and nascent stages of breakthrough innovations from the perspective of outliers,aiming t... Purpose:To address the“anomalies”that occur when scientific breakthroughs emerge,this study focuses on identifying early signs and nascent stages of breakthrough innovations from the perspective of outliers,aiming to achieve early identification of scientific breakthroughs in papers.Design/methodology/approach:This study utilizes semantic technology to extract research entities from the titles and abstracts of papers to represent each paper’s research content.Outlier detection methods are then employed to measure and analyze the anomalies in breakthrough papers during their early stages.The development and evolution process are traced using literature time tags.Finally,a case study is conducted using the key publications of the 2021 Nobel Prize laureates in Physiology or Medicine.Findings:Through manual analysis of all identified outlier papers,the effectiveness of the proposed method for early identifying potential scientific breakthroughs is verified.Research limitations:The study’s applicability has only been empirically tested in the biomedical field.More data from various fields are needed to validate the robustness and generalizability of the method.Practical implications:This study provides a valuable supplement to current methods for early identification of scientific breakthroughs,effectively supporting technological intelligence decision-making and services.Originality/value:The study introduces a novel approach to early identification of scientific breakthroughs by leveraging outlier analysis of research entities,offering a more sensitive,precise,and fine-grained alternative method compared to traditional citation-based evaluations,which enhances the ability to identify nascent breakthrough innovations. 展开更多
关键词 Scientific breakthroughs outlier analysis Research entities
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A Study on Outlier Detection and Feature Engineering Strategies in Machine Learning for Heart Disease Prediction
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作者 Varada Rajkumar Kukkala Surapaneni Phani Praveen +1 位作者 Naga Satya Koti Mani Kumar Tirumanadham Parvathaneni Naga Srinivasu 《Computer Systems Science & Engineering》 2024年第5期1085-1112,共28页
This paper investigates the application ofmachine learning to develop a response model to cardiovascular problems and the use of AdaBoost which incorporates an application of Outlier Detection methodologies namely;Z-S... This paper investigates the application ofmachine learning to develop a response model to cardiovascular problems and the use of AdaBoost which incorporates an application of Outlier Detection methodologies namely;Z-Score incorporated with GreyWolf Optimization(GWO)as well as Interquartile Range(IQR)coupled with Ant Colony Optimization(ACO).Using a performance index,it is shown that when compared with the Z-Score and GWO with AdaBoost,the IQR and ACO,with AdaBoost are not very accurate(89.0%vs.86.0%)and less discriminative(Area Under the Curve(AUC)score of 93.0%vs.91.0%).The Z-Score and GWO methods also outperformed the others in terms of precision,scoring 89.0%;and the recall was also found to be satisfactory,scoring 90.0%.Thus,the paper helps to reveal various specific benefits and drawbacks associated with different outlier detection and feature selection techniques,which can be important to consider in further improving various aspects of diagnostics in cardiovascular health.Collectively,these findings can enhance the knowledge of heart disease prediction and patient treatment using enhanced and innovativemachine learning(ML)techniques.These findings when combined improve patient therapy knowledge and cardiac disease prediction through the use of cutting-edge and improved machine learning approaches.This work lays the groundwork for more precise diagnosis models by highlighting the benefits of combining multiple optimization methodologies.Future studies should focus on maximizing patient outcomes and model efficacy through research on these combinations. 展开更多
关键词 Grey wolf optimization ant colony optimization Z-SCORE interquartile range(IQR) ADABOOST outlier
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Changepoint Detection with Outliers Based on RWPCA
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作者 Xin Zhang Sanzhi Shi Yuting Guo 《Journal of Applied Mathematics and Physics》 2024年第7期2634-2651,共18页
Changepoint detection faces challenges when outlier data are present. This paper proposes a multivariate changepoint detection method which is based on the robust WPCA projection direction and the robust RFPOP method,... Changepoint detection faces challenges when outlier data are present. This paper proposes a multivariate changepoint detection method which is based on the robust WPCA projection direction and the robust RFPOP method, RWPCA-RFPOP method. Our method is double robust which is suitable for detecting mean changepoints in multivariate normal data with high correlations between variables that include outliers. Simulation results demonstrate that our method provides strong guarantees on both the number and location of changepoints in the presence of outliers. Finally, our method is well applied in an ACGH dataset. 展开更多
关键词 RWPCA-RFPOP Double Robust outlier Detection Biweight Loss
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CLOF Based Outlier Detection Algorithm of Temperature Data for Ethylene Cracking Furnace
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作者 Yidan Xin Shaolin Hu +1 位作者 Wenzhuo Chen He Song 《Journal of Harbin Institute of Technology(New Series)》 CAS 2023年第4期50-57,共8页
The flue temperature is one of the important indicators to characterize the combustion state of an ethylene cracker furnace,the outliers of temperature data can lead to the false alarm.Conventional outlier detection a... The flue temperature is one of the important indicators to characterize the combustion state of an ethylene cracker furnace,the outliers of temperature data can lead to the false alarm.Conventional outlier detection algorithms such as the Isolation Forest algorithm and 3-sigma principle cannot detect the outliers accurately.In order to improve the detection accuracy and reduce the computational complexity,an outlier detection algorithm for flue temperature data based on the CLOF(Clipping Local Outlier Factor,CLOF)algorithm is proposed.The algorithm preprocesses the normalized data using the cluster pruning algorithm,and realizes the high accuracy and high efficiency outlier detection in the outliers candidate set.Using the flue temperature data of an ethylene cracking furnace in a petrochemical plant,the main parameters of the CLOF algorithm are selected according to the experimental results,and the outlier detection effect of the Isolation Forest algorithm,the 3-sigma principle,the conventional LOF algorithm and the CLOF algorithm are compared and analyzed.The results show that the appropriate clipping coefficient in the CLOF algorithm can significantly improve the detection efficiency and detection accuracy.Compared with the outlier detection results of the Isolation Forest algorithm and 3-sigma principle,the accuracy of the CLOF detection results is increased,and the amount of data calculation is significantly reduced. 展开更多
关键词 temperature data outlier detection ethylene cracker furnace CLUSTERING data clipping LOF
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A Novel Outlier Detection with Feature Selection Enabled Streaming Data Classification
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作者 R.Rajakumar S.Sathiya Devi 《Intelligent Automation & Soft Computing》 SCIE 2023年第2期2101-2116,共16页
Due to the advancements in information technologies,massive quantity of data is being produced by social media,smartphones,and sensor devices.The investigation of data stream by the use of machine learning(ML)approach... Due to the advancements in information technologies,massive quantity of data is being produced by social media,smartphones,and sensor devices.The investigation of data stream by the use of machine learning(ML)approaches to address regression,prediction,and classification problems have received consid-erable interest.At the same time,the detection of anomalies or outliers and feature selection(FS)processes becomes important.This study develops an outlier detec-tion with feature selection technique for streaming data classification,named ODFST-SDC technique.Initially,streaming data is pre-processed in two ways namely categorical encoding and null value removal.In addition,Local Correla-tion Integral(LOCI)is used which is significant in the detection and removal of outliers.Besides,red deer algorithm(RDA)based FS approach is employed to derive an optimal subset of features.Finally,kernel extreme learning machine(KELM)classifier is used for streaming data classification.The design of LOCI based outlier detection and RDA based FS shows the novelty of the work.In order to assess the classification outcomes of the ODFST-SDC technique,a series of simulations were performed using three benchmark datasets.The experimental results reported the promising outcomes of the ODFST-SDC technique over the recent approaches. 展开更多
关键词 Streaming data classification outlier removal feature selection machine learning metaheuristics
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Outliers rejection in similar image matching
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作者 Qingqing CHEN Junfeng YAO 《Virtual Reality & Intelligent Hardware》 2023年第2期171-187,共17页
Background Image matching is crucial in numerous computer vision tasks such as 3D reconstruction and simultaneous visual localization and mapping.The accuracy of the matching significantly impacted subsequent studies.... Background Image matching is crucial in numerous computer vision tasks such as 3D reconstruction and simultaneous visual localization and mapping.The accuracy of the matching significantly impacted subsequent studies.Because of their local similarity,when image pairs contain comparable patterns but feature pairs are positioned differently,incorrect recognition can occur as global motion consistency is disregarded.Methods This study proposes an image-matching filtering algorithm based on global motion consistency.It can be used as a subsequent matching filter for the initial matching results generated by other matching algorithms based on the principle of motion smoothness.A particular matching algorithm can first be used to perform the initial matching;then,the rotation and movement information of the global feature vectors are combined to effectively identify outlier matches.The principle is that if the matching result is accurate,the feature vectors formed by any matched point should have similar rotation angles and moving distances.Thus,global motion direction and global motion distance consistencies were used to reject outliers caused by similar patterns in different locations.Results Four datasets were used to test the effectiveness of the proposed method.Three datasets with similar patterns in different locations were used to test the results for similar images that could easily be incorrectly matched by other algorithms,and one commonly used dataset was used to test the results for the general image-matching problem.The experimental results suggest that the proposed method is more accurate than other state-of-the-art algorithms in identifying mismatches in the initial matching set.Conclusions The proposed outlier rejection matching method can significantly improve the matching accuracy for similar images with locally similar feature pairs in different locations and can provide more accurate matching results for subsequent computer vision tasks. 展开更多
关键词 Feature matching outlier removal Motion consistency Similar image matching Global structures
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A Study of Detection of Outliers for Working and Non-Working Days Air Quality in Kolkata, India: A Case Study
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作者 Mohammad Ahmad Weihu Cheng +1 位作者 Zhao Xu Abdul Kalam 《Journal of Environmental Protection》 2023年第8期685-709,共22页
A variety of factors affect air quality, making it a difficult issue. The level of clean air in a certain area is referred to as air quality. It is challenging for conventional approaches to correctly discover aberran... A variety of factors affect air quality, making it a difficult issue. The level of clean air in a certain area is referred to as air quality. It is challenging for conventional approaches to correctly discover aberrant values or outliers due to the significant fluctuation of this sort of data, which is influenced by Climate change and the environment. With accelerating industrial expansion and rising population density in Kolkata City, air pollution is continuously rising. This study involves two phases, in the first phase imputation of missing values and second detection of outliers using Statistical Process Control (SPC), and Functional Data Analysis (FDA), studies to achieve the efficacy of the outlier identification methodology proposed with working days and Nonworking days of the variables NO<sub>2</sub>, SO<sub>2</sub>, and O<sub>3</sub>, which were used for a year in a row in Kolkata, India. The results show how the functional data approach outshines traditional outlier detection methods. The outcomes show that functional data analysis vibrates more than the other two approaches after imputation, and the suggested outlier detector is absolutely appropriate for the precise detection of outliers in highly variable data. 展开更多
关键词 Statistical Process Control Functional Data Analysis Fuzzy C Means outlierS Air Quality
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Outlier Detection of Air Quality for Two Indian Urban Cities Using Functional Data Analysis
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作者 Mohammad Ahmad Weihu Cheng +1 位作者 Zhao Xu Abdul Kalam 《Open Journal of Air Pollution》 2023年第3期79-91,共13页
Human living would be impossible without air quality. Consistent advancements in practically every aspect of contemporary human life have harmed air quality. Everyday industrial, transportation, and home activities tu... Human living would be impossible without air quality. Consistent advancements in practically every aspect of contemporary human life have harmed air quality. Everyday industrial, transportation, and home activities turn up dangerous contaminants in our surroundings. This study investigated two years’ worth of air quality and outlier detection data from two Indian cities. Studies on air pollution have used numerous types of methodologies, with various gases being seen as a vector whose components include gas concentration values for each observation per-formed. We use curves to represent the monthly average of daily gas emissions in our technique. The approach, which is based on functional depth, was used to find outliers in the city of Delhi and Kolkata’s gas emissions, and the outcomes were compared to those from the traditional method. In the evaluation and comparison of these models’ performances, the functional approach model studied well. 展开更多
关键词 Functional Data Analysis outlierS Air Quality Gas Emission Classical Statistics
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基于快速SVDD的无线传感器网络Outlier检测 被引量:8
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作者 谢迎新 陈祥光 +2 位作者 余向明 岳彬 郭静 《仪器仪表学报》 EI CAS CSCD 北大核心 2011年第1期46-51,共6页
Outlier是基于无线传感器网络的数据收集应用中常见的数据故障类型,严重影响数据质量。本文提出一种基于快速SVDD的无线传感器网络Outlier检测方法,其基本思想是:首先利用快速SVDD算法获得包含正常样本的最小球形边界,然后通过该边界判... Outlier是基于无线传感器网络的数据收集应用中常见的数据故障类型,严重影响数据质量。本文提出一种基于快速SVDD的无线传感器网络Outlier检测方法,其基本思想是:首先利用快速SVDD算法获得包含正常样本的最小球形边界,然后通过该边界判断未知样本的类别,本法采用训练集约减策略和基于二阶逼近的SMO算法来加速SVDD的训练。基于合成数据和真实数据的仿真实验表明,该方法在确保分类精度的同时,运行速度快,内存开销小,适用于资源有限的无线传感器网络。 展开更多
关键词 无线传感器网络 outlier检测 SVDD 训练集约简 SMO算法
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η-one-class问题和η-outlier及其LP学习算法 被引量:1
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作者 陶卿 齐红威 +1 位作者 吴高巍 章显 《计算机学报》 EI CSCD 北大核心 2004年第8期1102-1108,共7页
用SVM方法研究one class和outlier问题 .在将one class问题理解为一种函数估计问题的基础上 ,作者首次定义了 η one class和 η outlier问题的泛化错误 ,进而定义了线性可分性和边缘 ,得到了求解one class问题的最大边缘、软边缘和ν ... 用SVM方法研究one class和outlier问题 .在将one class问题理解为一种函数估计问题的基础上 ,作者首次定义了 η one class和 η outlier问题的泛化错误 ,进而定义了线性可分性和边缘 ,得到了求解one class问题的最大边缘、软边缘和ν 软边缘算法 .这些学习算法具有统计学习理论依据并可归结为求解线性规划问题 .算法的实现采用与boosting类似的思路 .实验结果表明该文的算法是有实际意义的 . 展开更多
关键词 one-class问题 outlier 最大边缘 统计学习理论 支持向量机 线性规划问题 BOOSTING
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一类结合Outlier分析的单变量ARIMA模型在股票市场中的应用
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作者 曹韫建 《中国管理科学》 CSSCI 1998年第1期10-15,共6页
本文通过对当前广泛使用的经济时间序列预测方法的分析比较,针对如股票价格这一类易受到大量外部因素影响且难以通过多变量建模分析的经济现象,采用了单变量ARIMA模型并结合Outlier分析的方法。
关键词 单变量 ARIMA模型 应用 股票市场 outlier分析
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来自于Multiple-Outlier模型的最小次序统计量序性质(英文)
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作者 程美芳 方龙祥 杨芳 《应用概率统计》 CSCD 北大核心 2017年第3期317-330,共14页
本文中,我们研究来自于两个multiple-outlier模型的最小次序统计量的随机比较,其中两个模型中独立同分布的随机变量个数不同.令X_(1:n)(p,q)和X_(1:n~*)(p~*,q~*)分别表示来自于X_1,…,X_p,X_(p+1),…,X_n和X_1,…,X_(p),X_(p~*+1),…,X... 本文中,我们研究来自于两个multiple-outlier模型的最小次序统计量的随机比较,其中两个模型中独立同分布的随机变量个数不同.令X_(1:n)(p,q)和X_(1:n~*)(p~*,q~*)分别表示来自于X_1,…,X_p,X_(p+1),…,X_n和X_1,…,X_(p),X_(p~*+1),…,X_(n)的最小次序统计量,这里q=n-p,q~*=n~*-p~*.在参数(p,q)和(p~*,q~*)满足某些优化序条件下,我们根据普通随机序,失效率序和似然比序给出了X_(1:n)(p,q)和X_(1:n~*)(p~*,q~*)的序比较. 展开更多
关键词 multiple-outlier模型 普通随机序 失效率序 似然比序 最小次序统计量 比例失效率模型
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A Two-Level Approach based on Integration of Bagging and Voting for Outlier Detection
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作者 Alican Dogan Derya Birant 《Journal of Data and Information Science》 CSCD 2020年第2期111-135,共25页
Purpose:The main aim of this study is to build a robust novel approach that is able to detect outliers in the datasets accurately.To serve this purpose,a novel approach is introduced to determine the likelihood of an ... Purpose:The main aim of this study is to build a robust novel approach that is able to detect outliers in the datasets accurately.To serve this purpose,a novel approach is introduced to determine the likelihood of an object to be extremely different from the general behavior of the entire dataset.Design/methodology/approach:This paper proposes a novel two-level approach based on the integration of bagging and voting techniques for anomaly detection problems.The proposed approach,named Bagged and Voted Local Outlier Detection(BV-LOF),benefits from the Local Outlier Factor(LOF)as the base algorithm and improves its detection rate by using ensemble methods.Findings:Several experiments have been performed on ten benchmark outlier detection datasets to demonstrate the effectiveness of the BV-LOF method.According to the results,the BV-LOF approach significantly outperformed LOF on 9 datasets of 10 ones on average.Research limitations:In the BV-LOF approach,the base algorithm is applied to each subset data multiple times with different neighborhood sizes(k)in each case and with different ensemble sizes(T).In our study,we have chosen k and T value ranges as[1-100];however,these ranges can be changed according to the dataset handled and to the problem addressed.Practical implications:The proposed method can be applied to the datasets from different domains(i.e.health,finance,manufacturing,etc.)without requiring any prior information.Since the BV-LOF method includes two-level ensemble operations,it may lead to more computational time than single-level ensemble methods;however,this drawback can be overcome by parallelization and by using a proper data structure such as R*-tree or KD-tree.Originality/value:The proposed approach(BV-LOF)investigates multiple neighborhood sizes(k),which provides findings of instances with different local densities,and in this way,it provides more likelihood of outlier detection that LOF may neglect.It also brings many benefits such as easy implementation,improved capability,higher applicability,and interpretability. 展开更多
关键词 outlier detection Local outlier factor Ensemble learning BAGGING VOTING
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An Intelligent Early Warning Method of Press-Assembly Quality Based on Outlier Data Detection and Linear Regression
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作者 XUE Shanliang LI Chen 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2020年第4期597-606,共10页
Focusing on controlling the press-assembly quality of high-precision servo mechanism,an intelligent early warning method based on outlier data detection and linear regression is proposed.Linear regression is used to d... Focusing on controlling the press-assembly quality of high-precision servo mechanism,an intelligent early warning method based on outlier data detection and linear regression is proposed.Linear regression is used to deal with the relationship between assembly quality and press-assembly process,then the mathematical model of displacement-force in press-assembly process is established and a qualified press-assembly force range is defined for assembly quality control.To preprocess the raw dataset of displacement-force in the press-assembly process,an improved local outlier factor based on area density and P weight(LAOPW)is designed to eliminate the outliers which will result in inaccuracy of the mathematical model.A weighted distance based on information entropy is used to measure distance,and the reachable distance is replaced with P weight.Experiments show that the detection efficiency of the algorithm is improved by 5.6 ms compared with the traditional local outlier factor(LOF)algorithm,and the detection accuracy is improved by about 2%compared with the local outlier factor based on area density(LAOF)algorithm.The application of LAOPW algorithm and the linear regression model shows that it can effectively carry out intelligent early warning of press-assembly quality of high precision servo mechanism. 展开更多
关键词 quality early warning outlier data detection linear regression local outlier factor based on area density and P weight(LAOPW) information entropy P weight
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An Investigation of the Effect of the Swamping Phenomenon on Several Block Procedures for Multiple Outliers in Univariate Samples
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作者 Thomas W. Woolley 《Open Journal of Statistics》 2013年第5期229-304,共76页
In its broadest sense, this paper reviews the general outlier problem, the means available for addressing the discordancy (or lack thereof) of an outlier (or outliers), and possible strategies for dealing with them. T... In its broadest sense, this paper reviews the general outlier problem, the means available for addressing the discordancy (or lack thereof) of an outlier (or outliers), and possible strategies for dealing with them. Two alternate approaches to the multiple outlier problem, consecutive and block testing, and their respective inherent weaknesses, masking and swamping, are discussed. In addition, the relative susceptibility of several tests for outliers in normal samples to the swamping phenomena is reported. 展开更多
关键词 outlierS outlier Detection Swamping MASKING
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Probabilistic Automatic Outlier Detection for Surface Air Quality Measurements from the China National Environmental Monitoring Network 被引量:12
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作者 Huangjian WU Xiao TANG +4 位作者 Zifa WANG Lin WU Miaomiao LU Lianfang WEI Jiang ZHU 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2018年第12期1522-1532,共11页
Although quality assurance and quality control procedures are routinely applied in most air quality networks, outliers can still occur due to instrument malfunctions, the influence of harsh environments and the limita... Although quality assurance and quality control procedures are routinely applied in most air quality networks, outliers can still occur due to instrument malfunctions, the influence of harsh environments and the limitation of measuring methods. Such outliers pose challenges for data-powered applications such as data assimilation, statistical analysis of pollution characteristics and ensemble forecasting. Here, a fully automatic outlier detection method was developed based on the probability of residuals, which are the discrepancies between the observed and the estimated concentration values. The estimation can be conducted using filtering—or regressions when appropriate—to discriminate four types of outliers characterized by temporal and spatial inconsistency, instrument-induced low variances, periodic calibration exceptions, and less PM_(10) than PM_(2.5) in concentration observations, respectively. This probabilistic method was applied to detect all four types of outliers in hourly surface measurements of six pollutants(PM_(2.5), PM_(10),SO_2,NO_2,CO and O_3) from 1436 stations of the China National Environmental Monitoring Network during 2014-16. Among the measurements, 0.65%-5.68% are marked as outliers. with PM_(10) and CO more prone to outliers. Our method successfully identifies a trend of decreasing outliers from 2014 to 2016,which corresponds to known improvements in the quality assurance and quality control procedures of the China National Environmental Monitoring Network. The outliers can have a significant impact on the annual mean concentrations of PM_(2.5),with differences exceeding 10 μg m^(-3) at 66 sites. 展开更多
关键词 PROBABILISTIC AUTOMATIC outlier detection air quality observation low PASS filter spatial regression BIVARIATE normal distribution
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Density-based trajectory outlier detection algorithm 被引量:10
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作者 Zhipeng Liu Dechang Pi Jinfeng Jiang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2013年第2期335-340,共6页
With the development of global position system(GPS),wireless technology and location aware services,it is possible to collect a large quantity of trajectory data.In the field of data mining for moving objects,the pr... With the development of global position system(GPS),wireless technology and location aware services,it is possible to collect a large quantity of trajectory data.In the field of data mining for moving objects,the problem of anomaly detection is a hot topic.Based on the development of anomalous trajectory detection of moving objects,this paper introduces the classical trajectory outlier detection(TRAOD) algorithm,and then proposes a density-based trajectory outlier detection(DBTOD) algorithm,which compensates the disadvantages of the TRAOD algorithm that it is unable to detect anomalous defects when the trajectory is local and dense.The results of employing the proposed algorithm to Elk1993 and Deer1995 datasets are also presented,which show the effectiveness of the algorithm. 展开更多
关键词 density-based algorithm trajectory outlier detection(TRAOD) partition-and-detect framework Hausdorff distance
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Rough Outlier Detection Based Security Risk Analysis Methodology 被引量:13
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作者 Li Qianmu Li Jia 《China Communications》 SCIE CSCD 2012年第7期14-21,共8页
Security is a nonfunctional information system attribute that plays a crucial role in wide sensor network application domains. Security risk can be quantified as the combination of the probability that a sensor networ... Security is a nonfunctional information system attribute that plays a crucial role in wide sensor network application domains. Security risk can be quantified as the combination of the probability that a sensor network system may fail and the evaluation of the severity of the damage caused by the failure. In this paper, we devise a methodology of Rough Outlier Detection (ROD) for the detection of security-based risk factor, which originates from violations of attack requirements (namely, attack risks). The methodology elaborates dimension reduction method to analyze the attack risk probability from high dimensional and nonlinear data set, and combines it with rough redundancy reduction and the distance measurement of kernel function which is obtained using the ROD. In this way, it is possible to determine the risky scenarios, and the analysis feedback can be used to improve the sensor network system design. We illustrate the methodology in the DARPA case set study using step-by-step approach and then prove that the method is effective in lowering the rate of false alarm. 展开更多
关键词 rough outlier risk analysis dimensionality reduction
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GA-iForest: An Efficient Isolated Forest Framework Based on Genetic Algorithm for Numerical Data Outlier Detection 被引量:4
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作者 LI Kexin LI Jing +3 位作者 LIU Shuji LI Zhao BO Jue LIU Biqi 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2019年第6期1026-1038,共13页
With the development of data age,data quality has become one of the problems that people pay much attention to.As a field of data mining,outlier detection is related to the quality of data.The isolated forest algorith... With the development of data age,data quality has become one of the problems that people pay much attention to.As a field of data mining,outlier detection is related to the quality of data.The isolated forest algorithm is one of the more prominent numerical data outlier detection algorithms in recent years.In the process of constructing the isolation tree by the isolated forest algorithm,as the isolation tree is continuously generated,the difference of isolation trees will gradually decrease or even no difference,which will result in the waste of memory and reduced efficiency of outlier detection.And in the constructed isolation trees,some isolation trees cannot detect outlier.In this paper,an improved iForest-based method GA-iForest is proposed.This method optimizes the isolated forest by selecting some better isolation trees according to the detection accuracy and the difference of isolation trees,thereby reducing some duplicate,similar and poor detection isolation trees and improving the accuracy and stability of outlier detection.In the experiment,Ubuntu system and Spark platform are used to build the experiment environment.The outlier datasets provided by ODDS are used as test.According to indicators such as the accuracy,recall rate,ROC curves,AUC and execution time,the performance of the proposed method is evaluated.Experimental results show that the proposed method can not only improve the accuracy and stability of outlier detection,but also reduce the number of isolation trees by 20%-40%compared with the original iForest method. 展开更多
关键词 outlier detection isolation tree isolated forest genetic algorithm feature selection
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Outlier screening for ironmaking data on blast furnaces 被引量:6
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作者 Jun Zhao Shao-fei Chen +3 位作者 Xiao-jie Liu Xin Li Hong-yang Li Qing Lyu 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2021年第6期1001-1010,共10页
Blast furnace data processing is prone to problems such as outliers.To overcome these problems and identify an improved method for processing blast furnace data,we conducted an in-depth study of blast furnace data.Bas... Blast furnace data processing is prone to problems such as outliers.To overcome these problems and identify an improved method for processing blast furnace data,we conducted an in-depth study of blast furnace data.Based on data samples from selected iron and steel companies,data types were classified according to different characteristics;then,appropriate methods were selected to process them in order to solve the deficiencies and outliers of the original blast furnace data.Linear interpolation was used to fill in the divided continuation data,the Knearest neighbor(KNN)algorithm was used to fill in correlation data with the internal law,and periodic statistical data were filled by the average.The error rate in the filling was low,and the fitting degree was over 85%.For the screening of outliers,corresponding indicator parameters were added according to the continuity,relevance,and periodicity of different data.Also,a variety of algorithms were used for processing.Through the analysis of screening results,a large amount of efficient information in the data was retained,and ineffective outliers were eliminated.Standardized processing of blast furnace big data as the basis of applied research on blast furnace big data can serve as an important means to improve data quality and retain data value. 展开更多
关键词 blast furnace data missing outlierS data processing data mining
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