Homepage Thomas Opitz

Homepage of Thomas Opitz

I am a research associate ("chargé de recherche") at the Biostatistics and Spatial processes lab of INRA in Avignon.

How to reach me

Telephone: 04 32 72 21 86
Mail: thomas POINT opitz AT inra POINT fr

My main research interests

I am  interested in stochastic geometry and in spatial and spatiotemporal statistics with a view towards extreme values, often with a blend of frequentist and Bayesian inference techniques.

  • INLA-based inference of spatially structured Bayesian hierarchical models
    • log-Gaussian Cox processes for environmental risks (forest fires, landslides) and ecological processes
    • threshold exceedances
    • space-time trends in soil variables
  • Stochastic simulation of realistic agricultural landscapes using stochastic geometry tools
  • Multivariate and spatial extreme value analysis based on threshold exceedances
    • new models with flexible joint tail decay rates, often based on random scale mixtures
    • space-time modeling, space-time Gaussian scale mixtures
    • applications to meteorological and climatic processes (precipitation, wind speeds, temperatures, air pollution)
    • semiparametric resampling techniques for spatial and spatio-temporal extremes
  • Spatial and spatiotemporal models based on kernel convolutions
    • Gamma-Pareto processes for modeling threshold exceedances
    • count processes
  • Spatial and spatiotemporal modeling of plant and animal species

Some ongoing projects

  • Co-Investigator of the KAUST Competitive Research Grant "Statistical Estimation and Detection of Extreme Hot Spots, with Environmental and Ecological Applications"
    (coordinated by Raphael Huser, with partners at KAUST and Lancaster University)
  • Pari scientifique EA "Approches innovantes de prévisions géo-datées des propriétés des sols", coordinated by Hocine Bourennane and Nicolas Saby
  • Steering committee of RESSTE ("RESeau Statistique pour données Spatio-TEmporelles"), one of INRA's current research groups
  • Member and webmaster of the "Groupe Environnement et Statistique" of the French Statistical Society
  • LEFE-CERISE
    "Simulation de scénarii intégrant des champs extrêmes spatio-temporelle avec éventuelle indépendance asymptotique pour des études d'impact en science de l'environnement"

Preprints (needs updating...)

  1. Jean-Noel Bacro, Carlo Gaetan, Thomas Opitz, and Gwladys Toulemonde. Hierarchical space-time modeling of exceedances with an application to rainfall data. Submitted, 2017.
    Luigi Lombardo, Thomas Opitz, and Raphael Huser. Point process-based modeling of multiple debris flow landslides using inla: an application to the 2009 messina disaster. Submitted, 2017.
    Gabriel, E., Opitz, T., Bonneu, F.  Detecting and modeling multi-scale space-time structures: the case of wildfire occurrences. Submitted to Journal de la Société Française de Statistique (Special Issue on Space-Time Statistics). [pdf link]
    RESSTE Network. Analyzing spatio-temporal data with R: Everything you always wanted to know -- but were afraid to ask. Submitted to Journal de la Société Française de Statistique (Special Issue on Space-Time Statistics). [pdf link]

Publications (needs updating...)

Bayesian spatial modeling

Opitz, T. Latent Gaussian modeling and INLA: A review with focus on space-time applications. To appear in Journal of the French Statistical Society (Special Issue on Space-Time Statistics). [pdf link]

Extreme value analysis and risk

Huser, R., Opitz, T., Thibaud, E. Bridging Asymptotic Independence and Dependence in Spatial Extremes Using Gaussian Scale Mixtures . Spatial Statistics 21, 166–186 (2017). [arXiv]
Mornet, A., Opitz, T., Luzi, M., Loisel, S. & Bailleul, B. Wind Storm Risk Management: Sensitivity of Return Period Calculations and Spread on the Territory. Accepted for Stochastic Environmental Research and Risk Assessment.
Opitz, T. Modeling asymptotically independent spatial extremes based on Laplace random fields. Spatial Statistics 16, 1–18 (2016). [arXiv]
Thibaud, E. & Opitz, T. Efficient inference and simulation for elliptical Pareto processes. Biometrika 102(4), 855–870 (2015).
Mornet, A., Opitz, T., Luzi, M. & Loisel, S. Index for Predicting Insurance Claims from Wind Storms with an Application in France. Risk Analysis 35(11), 2029–2056 (2015).
Opitz, T., Bacro, J.-N. & Ribereau, P. The spectrogram: A threshold-based inferential tool for extremes of stochastic processes. Electronic Journal of Statistics 9, 842–868 (2015). [open access link]
Opitz, T. Extremal processes: Elliptical domain of attraction and a spectral representation. Journal of Multivariate Analysis 122, 409–413 (2013). [arXiv]

Text mining

Donald Tapi Nzali, Mike and Azé, Jérôme and Bringay, Sandra and Lavergne, Christian and Mollevi, Caroline and Opitz, Thomas. What Patients Can Tell Us: Topic Analysis for Social Media on Breast Cancer. Journal of Medical Internet Research, 2017.
Donald Tapi Nzali, M., Azé, J., Bringay, S., Lavergne, C., Mollevi, C. & Opitz, T. Formalisation semi-automatique d'un vocabulaire Patient/Médecin dédié au cancer du sein. Revue d'Intelligence Artificielle, Numéro spécial IC 2014/2015.
Opitz, T. et al. Breast cancer and quality of life: medical information extraction from health forums. in Medical Informatics Europe, pages 1070–1074 (2014).
Opitz, T. et al. Paroles de patients dans les forums de santé: une perspective originale sur la qualité de la vie. in 25es Journées francophones d’Ingénierie des Connaissances, Actes de l’Atelier IA & Santé (2014).

Other

Opitz, T. Extrêmes multivariés et spatiaux: approches spectrales et modèles elliptiques. (PhD Thesis, University of Montpellier, 2013).
Opitz, T., Tramini, P. & Molinari, N. Spline regression for zero-inflated models. JP Journal of Biostatistics 9(1), 53–66 (2013).

Current responsibilities

  • Co-organizer of the weekly seminar of BioSP
  • Webmaster of the GdR GeoSto Meeting 2019 in Avignon

Past responsibilities

  • Vice-president of organizing committee and webmaster (web site and registration, submission, review systems) of the METMA IX conference on Space-time modeling and statistics,  13-15 June  2018, Montpellier
  • Webmaster (web site and registration, submission, review systems) of the Journées de Statistique 2017, Avignon
  • Organization and Program Committee of AG MIA 2017 / Journées Maths-Infos / Journées INRA-Inria
  • Program Committee of Spatial Statistics 2015, Avignon

Teaching

  • 2018- : I am responsible for the course "Statistique spatiale et écologie", M2 Data Science, Marseille
  • 2016/2017: Statistique Descriptive 2, L1 STID, IUT Avignon