Gyarmati-Szabo, J, Bogachev, LV and Chen, H (2017) Nonstationary POT modelling of air pollution concentrations: Statistical analysis of the traffic and meteorological impact. Environmetrics, 28 (5). ISSN 1180-4009
Abstract
Predicting the occurrence, level, and duration of high air pollution concentrations exceeding a given critical level enables researchers to study the health impact of road traffic on local air quality and to inform public policy action. Precise estimates of the probabilities of occurrence and level of extreme concentrations are formidable due to the combination of complex physical and chemical processes involved. This underpins the need for developing sophisticated extreme value models, in particular allowing for nonstationarity of environmental time series. In this paper, extremes of nitrogen oxide (NO), nitrogen dioxide (NO2), and ozone (O3) concentrations are investigated using two models. Model I is based on an extended peaks-over-threshold (POT) approach developed by A. C. Davison and R. L. Smith, whereby the parameters of the underlying generalized Pareto distribution (GPD) are treated as functions of covariates (i.e., traffic and meteorological factors). The new Model II resolves the lack of threshold stability in the Davison–Smith model by constructing a special functional form for the GPD parameters. For each of the models, the effects of traffic and meteorological factors on the frequency and size of extreme values are estimated using Markov chain Monte Carlo methods. Finally, appropriate goodness-of-fit tests and model selection criteria confirm that Model II significantly outperforms Model I in estimation and forecasting of extremes.
Metadata
Item Type: | Article |
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Authors/Creators: |
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Copyright, Publisher and Additional Information: | © 2017 John Wiley & Sons, Ltd. This is the peer reviewed version of the following article: Gyarmati-Szabó J, Bogachev LV, Chen H. Nonstationary POT modelling of air pollution concentrations: Statistical analysis of the traffic and meteorological impact. Environmetrics. 2017; e2449, which has been published in final form at https://doi.org/10.1002/env.2449. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving. Uploaded in accordance with the publisher's self-archiving policy. |
Keywords: | extreme values; generalized Pareto distribution (GPD); nonstationarity; peaks-over-threshold (POT); roadside air pollution; threshold stability |
Dates: |
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Institution: | The University of Leeds |
Academic Units: | The University of Leeds > Faculty of Environment (Leeds) > Institute for Transport Studies (Leeds) > ITS: Spatial Modelling and Dynamics (Leeds) The University of Leeds > Faculty of Engineering & Physical Sciences (Leeds) > School of Mathematics (Leeds) > Statistics (Leeds) |
Funding Information: | Funder Grant number EPSRC EP/E002013/1 |
Depositing User: | Symplectic Publications |
Date Deposited: | 07 Jun 2017 09:27 |
Last Modified: | 04 Jun 2018 00:39 |
Status: | Published |
Publisher: | Wiley |
Identification Number: | 10.1002/env.2449 |
Open Archives Initiative ID (OAI ID): | oai:eprints.whiterose.ac.uk:117390 |