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Miller C, Portlock T, Nyaga DM, O'Sullivan JM. A review of model evaluation metrics for machine learning in genetics and genomics. FRONTIERS IN BIOINFORMATICS 2024; 4:1457619. [PMID: 39318760 PMCID: PMC11420621 DOI: 10.3389/fbinf.2024.1457619] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2024] [Accepted: 08/27/2024] [Indexed: 09/26/2024] Open
Abstract
Machine learning (ML) has shown great promise in genetics and genomics where large and complex datasets have the potential to provide insight into many aspects of disease risk, pathogenesis of genetic disorders, and prediction of health and wellbeing. However, with this possibility there is a responsibility to exercise caution against biases and inflation of results that can have harmful unintended impacts. Therefore, researchers must understand the metrics used to evaluate ML models which can influence the critical interpretation of results. In this review we provide an overview of ML metrics for clustering, classification, and regression and highlight the advantages and disadvantages of each. We also detail common pitfalls that occur during model evaluation. Finally, we provide examples of how researchers can assess and utilise the results of ML models, specifically from a genomics perspective.
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Affiliation(s)
- Catriona Miller
- The Liggins Institute, The University of Auckland, Auckland, New Zealand
| | - Theo Portlock
- The Liggins Institute, The University of Auckland, Auckland, New Zealand
| | - Denis M Nyaga
- The Liggins Institute, The University of Auckland, Auckland, New Zealand
| | - Justin M O'Sullivan
- The Liggins Institute, The University of Auckland, Auckland, New Zealand
- The Maurice Wilkins Centre, The University of Auckland, Auckland, New Zealand
- MRC Lifecourse Epidemiology Unit, University of Southampton, Southampton, United Kingdom
- Singapore Institute for Clinical Sciences, Agency for Science Technology and Research, Singapore, Singapore
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2
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López-Pintado D, López-Pintado S, García-Milán I, Yao Z. Uncertainty analysis of contagion processes based on a functional approach. Sci Rep 2023; 13:15522. [PMID: 37726315 PMCID: PMC10509249 DOI: 10.1038/s41598-023-42041-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2022] [Accepted: 09/04/2023] [Indexed: 09/21/2023] Open
Abstract
The spread of a disease, product or idea in a population is often hard to predict. We tend to observe one or few realizations of the contagion process and therefore limited information can be obtained for anticipating future similar events. The stochastic nature of contagion generates unpredictable outcomes throughout the whole course of the dynamics. This might lead to important inaccuracies in the predictions and to the over or under-reaction of policymakers, who tend to anticipate the average behavior. Through an extensive simulation study, we analyze properties of the contagion process, focusing on its unpredictability or uncertainty, and exploiting the functional nature of the data. In particular, we define a novel non-parametric measure of variance based on weighted depth-based central regions. We apply this methodology to the susceptible-infected-susceptible epidemiological model and small-world networks. We find that maximum uncertainty is attained at the epidemic threshold. The density of the network and the contagiousness of the process have a strong and complementary effect on the uncertainty of contagion, whereas only a mild effect of the network's randomness structure is observed.
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Affiliation(s)
| | - Sara López-Pintado
- Department of Health Sciences, Northeastern University, Boston, 02115-5005, USA.
| | - Iván García-Milán
- Engineering Department, Universidad de Loyola, 41704, Seville, Spain
| | - Zonghui Yao
- Department of Health Sciences, Northeastern University, Boston, 02115-5005, USA
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3
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Depth-based reconstruction method for incomplete functional data. Comput Stat 2022. [DOI: 10.1007/s00180-022-01282-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
AbstractThe problem of estimating missing fragments of curves from a functional sample has been widely considered in the literature. However, most reconstruction methods rely on estimating the covariance matrix or the components of its eigendecomposition, which may be difficult. In particular, the estimation accuracy might be affected by the complexity of the covariance function, the noise of the discrete observations, and the poor availability of complete discrete functional data. We introduce a non-parametric alternative based on depth measures for partially observed functional data. Our simulations point out that the benchmark methods perform better when the data come from one population, curves are smooth, and there is a large proportion of complete data. However, our approach is superior when considering more complex covariance structures, non-smooth curves, and when the proportion of complete functions is scarce. Moreover, even in the most severe case of having all the functions incomplete, our method provides good estimates; meanwhile, the competitors are unable. The methodology is illustrated with two real data sets: the Spanish daily temperatures observed in different weather stations and the age-specific mortality by prefectures in Japan. They highlight the interpretability potential of the depth-based method.
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Localization processes for functional data analysis. ADV DATA ANAL CLASSI 2022. [DOI: 10.1007/s11634-022-00512-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/15/2022]
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5
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Cholaquidis A, Fraiman R, Gamboa F, Moreno L. Weighted lens depth: Some applications to supervised classification. CAN J STAT 2022. [DOI: 10.1002/cjs.11724] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
| | - Ricardo Fraiman
- Facultad de Ciencias, Universidad de la República Montevideo 11400 Uruguay
| | - Fabrice Gamboa
- Institut de Mathématiques de Toulouse Toulouse 31400 France
| | - Leonardo Moreno
- Facultad de Ciencias Económicas, Universidad de la República Montevideo 112002 Uruguay
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Elías A, Jiménez R, Paganoni AM, Sangalli LM. Integrated Depths for Partially Observed Functional Data. J Comput Graph Stat 2022. [DOI: 10.1080/10618600.2022.2070171] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Affiliation(s)
- Antonio Elías
- OASYS Group, Department of Applied Mathematics, Universidad de Málaga
| | - Raúl Jiménez
- Department of Statistics, University Carlos III of Madrid
| | - Anna M. Paganoni
- MOX Laboratory for Modeling and Scientic Computing, Dipartimento di Matematica, Politecnico di Milano
| | - Laura M. Sangalli
- MOX Laboratory for Modeling and Scientic Computing, Dipartimento di Matematica, Politecnico di Milano
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7
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Pandolfo G. The GLD-plot: a depth-based graphical tool to investigate unimodality of directional data. J STAT COMPUT SIM 2022. [DOI: 10.1080/00949655.2022.2029445] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Affiliation(s)
- Giuseppe Pandolfo
- Department of Economics and Statistics, University of Naples Federico II, Napoli, Italy
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8
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Dai X, Lopez-Pintado S. Tukey's Depth for Object Data. J Am Stat Assoc 2022; 118:1760-1772. [PMID: 37791295 PMCID: PMC10545316 DOI: 10.1080/01621459.2021.2011298] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2021] [Accepted: 11/22/2021] [Indexed: 10/19/2022]
Abstract
We develop a novel exploratory tool for non-Euclidean object data based on data depth, extending celebrated Tukey's depth for Euclidean data. The proposed metric halfspace depth, applicable to data objects in a general metric space, assigns to data points depth values that characterize the centrality of these points with respect to the distribution and provides an interpretable center-outward ranking. Desirable theoretical properties that generalize standard depth properties postulated for Euclidean data are established for the metric halfspace depth. The depth median, defined as the deepest point, is shown to have high robustness as a location descriptor both in theory and in simulation. We propose an efficient algorithm to approximate the metric halfspace depth and illustrate its ability to adapt to the intrinsic data geometry. The metric halfspace depth was applied to an Alzheimer's disease study, revealing group differences in the brain connectivity, modeled as covariance matrices, for subjects in different stages of dementia. Based on phylogenetic trees of 7 pathogenic parasites, our proposed metric halfspace depth was also used to construct a meaningful consensus estimate of the evolutionary history and to identify potential outlier trees.
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Affiliation(s)
- Xiongtao Dai
- Department of Statistics, Iowa State University, Ames, Iowa 50011 USA
| | - Sara Lopez-Pintado
- Department of Health Sciences, Northeastern University, Boston, MA 02115 USA
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Data Depth-Based Nonparametric Tests for Multivariate Scales. JOURNAL OF STATISTICAL THEORY AND PRACTICE 2022. [DOI: 10.1007/s42519-021-00236-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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10
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Demni H, Messaoud A, Porzio GC. Distance-based directional depth classifiers: a robustness study. COMMUN STAT-SIMUL C 2021. [DOI: 10.1080/03610918.2021.1996603] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Affiliation(s)
- Houyem Demni
- Department of Economics and Law, University of Cassino and Southern Lazio, Cassino, Italy
| | - Amor Messaoud
- Laboratoire LEGI, Ecole Polytechnique de Tunisie, Université de Carthage, Tunis, Tunisia
| | - Giovanni C. Porzio
- Department of Economics and Law, University of Cassino and Southern Lazio, Cassino, Italy
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Affiliation(s)
| | | | - Myriam Vimond
- Univ Rennes, Ensai, CNRS, CREST – UMR 9194, Bruz, France
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Zhang X, Tian Y, Guan G, Gel YR. Depth-based classification for relational data with multiple attributes. J MULTIVARIATE ANAL 2021. [DOI: 10.1016/j.jmva.2021.104732] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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13
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Nagy S, Helander S, Van Bever G, Viitasaari L, Ilmonen P. Flexible integrated functional depths. BERNOULLI 2021. [DOI: 10.3150/20-bej1254] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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Dvořák J, Hudecová Š, Nagy S. Clover plot: Versatile visualization in nonparametric classification*. Stat Anal Data Min 2020. [DOI: 10.1002/sam.11481] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Jiří Dvořák
- Faculty of Mathematics and Physics, Department of Probability and Mathematical Statistics Charles University Prague Czech Republic
| | - Šárka Hudecová
- Faculty of Mathematics and Physics, Department of Probability and Mathematical Statistics Charles University Prague Czech Republic
| | - Stanislav Nagy
- Faculty of Mathematics and Physics, Department of Probability and Mathematical Statistics Charles University Prague Czech Republic
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Fortunato F, Anderlucci L, Montanari A. One‐class classification with application to forensic analysis. J R Stat Soc Ser C Appl Stat 2020. [DOI: 10.1111/rssc.12438] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Yuan Y, Liu X, Chen Y, Dong Y, Liu Y. On similarity of the sample projection depth contours and its application. COMMUN STAT-THEOR M 2020. [DOI: 10.1080/03610926.2020.1802651] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Affiliation(s)
- Yefang Yuan
- School of Statistics, Jiangxi University of Finance and Economics, Nanchang, China
- Business School, University of Sydney, Sydney, Australia
| | - Xiaohui Liu
- School of Statistics, Jiangxi University of Finance and Economics, Nanchang, China
- Research Center of Applied Statistics, Jiangxi University of Finance and Economics, Nanchang, China
| | - Yuting Chen
- School of Statistics, Jiangxi University of Finance and Economics, Nanchang, China
- Research Center of Applied Statistics, Jiangxi University of Finance and Economics, Nanchang, China
| | - Yuxin Dong
- School of Statistics, Jiangxi University of Finance and Economics, Nanchang, China
- Research Center of Applied Statistics, Jiangxi University of Finance and Economics, Nanchang, China
| | - Yuzi Liu
- School of Statistics, Jiangxi University of Finance and Economics, Nanchang, China
- Research Center of Applied Statistics, Jiangxi University of Finance and Economics, Nanchang, China
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19
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Affiliation(s)
- Stanislav Nagy
- Department of Probability and Mathematical Statistics, Faculty of Mathematics and Physics, Charles University, Prague, Czech Republic
| | - Jiří Dvořák
- Department of Probability and Mathematical Statistics, Faculty of Mathematics and Physics, Charles University, Prague, Czech Republic
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20
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Liu X, He Y. RR-plot: a descriptive tool for regression observations. J Appl Stat 2020; 47:76-90. [DOI: 10.1080/02664763.2019.1631268] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Affiliation(s)
- Xiaohui Liu
- School of Statistics, Jiangxi University of Finance and Economics, Nanchang Jiangxi, People's Republic of China
- Research Center of Applied Statistics, Jiangxi University of Finance and Economics, Nanchang, Jiangxi, People's Republic of China
| | - Yang He
- School of Statistics, Jiangxi University of Finance and Economics, Nanchang Jiangxi, People's Republic of China
- Research Center of Applied Statistics, Jiangxi University of Finance and Economics, Nanchang, Jiangxi, People's Republic of China
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21
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Tian Y, Gel YR. Fusing data depth with complex networks: Community detection with prior information. Comput Stat Data Anal 2019. [DOI: 10.1016/j.csda.2019.01.007] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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22
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23
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NITPicker: selecting time points for follow-up experiments. BMC Bioinformatics 2019; 20:166. [PMID: 30940082 PMCID: PMC6444531 DOI: 10.1186/s12859-019-2717-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2018] [Accepted: 03/06/2019] [Indexed: 02/03/2023] Open
Abstract
Background The design of an experiment influences both what a researcher can measure, as well as how much confidence can be placed in the results. As such, it is vitally important that experimental design decisions do not systematically bias research outcomes. At the same time, making optimal design decisions can produce results leading to statistically stronger conclusions. Deciding where and when to sample are among the most critical aspects of many experimental designs; for example, we might have to choose the time points at which to measure some quantity in a time series experiment. Choosing times which are too far apart could result in missing short bursts of activity. On the other hand, there may be time points which provide very little information regarding the overall behaviour of the quantity in question. Results In this study, we develop a tool called NITPicker (Next Iteration Time-point Picker) for selecting optimal time points (or spatial points along a single axis), that eliminates some of the biases caused by human decision-making, while maximising information about the shape of the underlying curves. NITPicker uses ideas from the field of functional data analysis. NITPicker is available on the Comprehensive R Archive Network (CRAN) and code for drawing figures is available on Github (https://github.com/ezer/NITPicker). Conclusions NITPicker performs well on diverse real-world datasets that would be relevant for varied biological applications, including designing follow-up experiments for longitudinal gene expression data, weather pattern changes over time, and growth curves. Electronic supplementary material The online version of this article (10.1186/s12859-019-2717-5) contains supplementary material, which is available to authorized users.
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24
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Liu X, Mosler K, Mozharovskyi P. Fast Computation of Tukey Trimmed Regions and Median in Dimension p > 2. J Comput Graph Stat 2019. [DOI: 10.1080/10618600.2018.1546595] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Affiliation(s)
- Xiaohui Liu
- School of Statistics, Research Center of Applied Statistics, Jiangxi University of Finance and Economics, Nanchang, China
| | - Karl Mosler
- Institute of Econometrics and Statistics, University of Cologne, Köln, Germany
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Chau J, Ombao H, von Sachs R. Intrinsic Data Depth for Hermitian Positive Definite Matrices. J Comput Graph Stat 2019. [DOI: 10.1080/10618600.2018.1537926] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Affiliation(s)
- Joris Chau
- Institute of Statistics, Biostatistics, and Actuarial Sciences, Université Catholique de Louvain, Louvain-la-Neuve, Belgium
| | - Hernando Ombao
- Department of Statistics, University of California at Irvine, Irvine, CA
- Department of Applied Mathematics and Computational Science, King Abdullah University of Science and Technology, Thuwal, Saudi Arabia
| | - Rainer von Sachs
- Institute of Statistics, Biostatistics, and Actuarial Sciences, Université Catholique de Louvain, Louvain-la-Neuve, Belgium
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27
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Affiliation(s)
- Giuseppe Pandolfo
- Department of Industrial Engineering; University of Naples Federico II; 80125 Naples Italy
| | - Davy Paindaveine
- ECARES and Département de Mathématique; Université libre de Bruxelles; Brussels 1050 Belgium
| | - Giovanni C. Porzio
- Department of Economics and Law; University of Cassino and Southern Lazio; 03043 Cassino Italy
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Affiliation(s)
- Jun Li
- Department of Statistics, University of California, Riverside, CA, USA
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Makinde OS, Fasoranbaku OA. On maximum depth classifiers: depth distribution approach. J Appl Stat 2018. [DOI: 10.1080/02664763.2017.1342783] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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33
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Pawar SD, Shirke DT. Nonparametric tests for multivariate locations based on data depth. COMMUN STAT-SIMUL C 2017. [DOI: 10.1080/03610918.2017.1397165] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Affiliation(s)
- Somanath D. Pawar
- Department of Statistics, Shivaji University, Kolhapur, Maharashtra, India
| | - Digambar T. Shirke
- Department of Statistics, Shivaji University, Kolhapur, Maharashtra, India
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Affiliation(s)
- Olusola Makinde
- School of Mathematics, University of Birmingham, Birmingham, United Kingdom
- Department of Statistics, Federal University of Technology, Akure, Nigeria
| | - Biman Chakraborty
- School of Mathematics, University of Birmingham, Birmingham, United Kingdom
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35
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Component-wise outlier detection methods for robustifying multivariate functional samples. Stat Pap (Berl) 2017. [DOI: 10.1007/s00362-017-0953-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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36
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Kim S, Mun BM, Bae SJ. Data depth based support vector machines for predicting corporate bankruptcy. APPL INTELL 2017. [DOI: 10.1007/s10489-017-1011-3] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Makinde OS, Adewumi AD. A comparison of depth functions in maximal depth classification rules. JOURNAL OF MODERN APPLIED STATISTICAL METHODS 2017. [DOI: 10.22237/jmasm/1493598120] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Masiol M, Squizzato S, Formenton G, Harrison RM, Agostinelli C. Air quality across a European hotspot: Spatial gradients, seasonality, diurnal cycles and trends in the Veneto region, NE Italy. THE SCIENCE OF THE TOTAL ENVIRONMENT 2017; 576:210-224. [PMID: 27788436 DOI: 10.1016/j.scitotenv.2016.10.042] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/30/2016] [Revised: 10/05/2016] [Accepted: 10/06/2016] [Indexed: 06/06/2023]
Abstract
The Veneto region (NE Italy) lies in the eastern part of the Po Valley, a European hotspot for air pollution. Data for key air pollutants (CO, NO, NO2, O3, SO2, PM10 and PM2.5) measured over 7years (2008/2014) across 43 sites in Veneto were processed to characterise their spatial and temporal patterns and assess the air quality. Nitrogen oxides, PM and ozone are critical pollutants frequently breaching the EC limit and target values. Intersite analysis demonstrates a widespread pollution across the region and shows that primary pollutants (nitrogen oxides, CO, PM) are significantly higher in cities and over the flat lands due to higher anthropogenic pressures. The spatial variation of air pollutants at rural sites was then mapped to depict the gradient of background pollution: nitrogen oxides are higher in the plain area due to the presence of strong diffuse anthropogenic sources, while ozone increases toward the mountains probably due to the higher levels of biogenic ozone-precursors and low NO emissions which are not sufficient to titrate out the photochemical O3. Data-depth classification analysis revealed a poor categorization among urban, traffic and industrial sites: weather and urban planning factors may cause a general homogeneity of air pollution within cities driving this poor classification. Seasonal and diurnal cycles were investigated: the effect of primary sources in populated areas is evident throughout the region and drives similar patterns for most pollutants: road traffic appears the predominant potential source shaping the daily cycles. Trend analysis of experimental data reveals a general decrease of air pollution across the region, which agrees well with changes assessed by emission inventories. This study provides key information on air quality across NE Italy and highlights future research needs and possible developments of the regional monitoring network.
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Affiliation(s)
- Mauro Masiol
- Center for Air Resources Engineering and Science, Clarkson University, Box 5708, Potsdam, NY 13699-5708, USA; Division of Environmental Health and Risk Management, School of Geography, Earth and Environmental Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, United Kingdom.
| | - Stefania Squizzato
- Center for Air Resources Engineering and Science, Clarkson University, Box 5708, Potsdam, NY 13699-5708, USA; Dipartimento Scienze Ambientali, Informatica e Statistica, Università Ca' Foscari Venezia, Campus Scientifico via Torino 155, 30170 Venezia, Italy
| | - Gianni Formenton
- Dipartimento Regionale Laboratori, Agenzia Regionale per la Prevenzione e Protezione Ambientale del Veneto, Via Lissa 6, 30174 Mestre, Italy
| | - Roy M Harrison
- Division of Environmental Health and Risk Management, School of Geography, Earth and Environmental Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, United Kingdom
| | - Claudio Agostinelli
- Dipartimento di Matematica, Università degli Studi di Trento, via Sommarive 14, Povo, Trento, Italy
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Affiliation(s)
| | - Vijayan N. Nair
- Department of Statistics, University of Michigan, Ann Arbor, MI, USA
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41
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Classification with the pot–pot plot. Stat Pap (Berl) 2016. [DOI: 10.1007/s00362-016-0854-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Comments on: Probability enhanced effective dimension reduction for classifying sparse functional data. TEST-SPAIN 2016. [DOI: 10.1007/s11749-015-0476-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Einmahl JHJ, Li J, Liu RY. Bridging centrality and extremity: Refining empirical data depth using extreme value statistics. Ann Stat 2015. [DOI: 10.1214/15-aos1359] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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50
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Integrated data depth for smooth functions and its application in supervised classification. Comput Stat 2015. [DOI: 10.1007/s00180-015-0566-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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