Dr Didier G. Leibovici is a Senior Research Fellow in geocomputational modelling & geospatial statistics at the Nottingham Geospatial Institute. Didier's career started as a statistician in epidemiology at the INSERM (France), where, whilst doing his PhD, he contributed to few longitudinal studies (HIV, cognitive decline, Athma mortality), then in medical imaging in the industry and at the university of Oxford (UK). Didier pursued his training in information technology and geoinformatics and worked for IRD (France) on GIS process modelling and data infrastructure in ecological monitoring. Since 2006 at the University of Nottingham (UK) and recenty at the University of Leeds, he combines these two aspects in research on the best use of interoperability for geospatial data in applied contexts.
Deepening his interests about integrated modelling within the spatio-temporal realm, applied in the fields of ecological modelling and public health/epidemiological studies, his approach focuses on meta-information, conflation models and spatial associations that can also benefits from the developments of interoperable framework such as GEOSS. These broad interests focus in particular on geoworkflow modelling and in spatial structuring of information.
For geoworkflow modelling Didier focuses on cross-scale issues and to chaining/combining models or services for integrated modelling applications within an interoperable framework such as the Spatial Data Infrastructure implemented by the GEOSS. This latter topic encompasses data quality and the impact of uncertainty in relation to the workflow used, together with sensitivity assessments, also when modifying the workflow due to change of context, e.g. upscaling, downscaling, in space and/or in time (cf., meta-propagation of uncertainties). This particular field of research is related to the uncertainty propagation in complex computer model.
In spatial structuring of information Didier's research investigates, on one hand, on the methods to analyse the interaction/association of univariate and multivariate spatial processes, and on the other hand, on capturing or simulating geolocated information. The first aspect focuses on both, statistical indicators of spatial structuring information (e.g. spatial clustering, outbreak detection) mainly coming from deriving spatial entropy based methods, and on the description of interactions via for example multiway multidimensional analysis (cf., the PTAk R-package and the under development kOO R-package). The other aspect focuses on developing spatial algorithms, geocomputational models and data infrastructure architecture to capture (e.g., VGI), integrate (e.g., data fusion, conflation), simulate or spatialise the information, for example due to a change of scale or geometry. From simulations this can also lead to inferential methods, then linking back to geoworlflow modelling in term of quality assessments as well as in data integration.
Dr Leibovici has a broad experience of large collaborative European projects from his contribution in DeSurvey (FP6) about desertification and ecological monitoring, eSoTer (FP7) about global soil and terrain databases to contribute to GEOSS, GIS4EU (FP7) on data harmonisation, GIGAS (FP7) action in support for convergence of the GEOSS, INSPIRE and GMES initiatives, EuroGEOSS (FP7) on multidisciplinary interoperability in geosciences disciplines involved in forestry, biodiversity, and drought, and recently in COBWEB (FP7), citizen observatory web, on data fusion of crowdsouced information with authoritative data for environmental governance in biosphere reserves (UNESCO Man and Biosphere program, World Network of Biosphere Reserves (WNBR)). He also contributed to Research Council projects, e.g. in TALISMAN (geosTapial datA anaLysIS and siMulAtioN) - ESRC, and GRASP-GFS (Geospatial Resource for Agricultural Species and Pests with integrated workflow modelling to support Global Fodd Security) - BBSRC.
COBWEB and GRASP (see Tab)
Didier's Research is related to interoperability and conflation models in geospatial analysis and integrated modelling applications, particularly in the context of spatial data infrastructures such… read more
STOCK, KRISTIN, LEIBOVICI, DIDIER, DELAZARI, LUCIENE and SANTOS, ROBERTO, 2015. Discovering Order in Chaos: Using a Heuristic Ontology to Derive Spatio-Temporal Sequences for Cadastral Data Spatial Cognition & Computation. 15(2), 115-141 LEIBOVICI, DIDIER G., CLARAMUNT, CHRISTOPHE, LE GUYADER, DAMIEN and BROSSET, DAVID, 2014. Local and global spatio-temporal entropy indices based on distance-ratios and co-occurrences distributions International Journal of Geographical Information Science. 28(5), 1061-1084
LEIBOVICI, D.G., POURABDOLLAH, A. and JACKSON, M.J., 2013. Which spatial data quality can be meta-propagated? Journal of Spatial Science. 58(1), 3-14
Didier's Research is related to interoperability and conflation models in geospatial analysis and integrated modelling applications, particularly in the context of spatial data infrastructures such as GEOSS. This translates to a focus on geocomputational statistics and data mining including geospatial patterns, outbreak detection, but also on geoworkflow modelling and partcularly to data quality and uncertainty propagation principles in relation to geoworkflows connected to/using web services. Didier's research centres on environmental agro-ecological geospatial models, and public health and spatial epidemiology applications.
in Geocomputational Data Association and Conflation
Geospatial Integrated Modelling:
The colourful summary presented above encompass for example the Integrated Modelling endeavour of many researchers: workflow example below in environmental modelling. Integrated Modelling fits into the theme ofGeospatial Data Association and Fusion . Data and models are becoming more and more easily available within the growing interoperable world of internet with focused repositories such as the GEOSS (geoportal) Combining by few clicks and drops all these resources from data and geoprocessing services may lead to uncontrolled outcomes. This work involves development of methods, measures, standards to derive meta-information of the quality and sensitivity of such workflows. Such methodology may be used to assist day to day researchers and analysts, in building model applications using geospatial information from different sources, at different scales, geoprocessed locally or remotely with various user objectives.
Geocomputational statistics and data mining:
Looking now, more the complexity of systems with multivariate observations in a spatio-temporal domain, sometimes as part of an integrated modelling analysis, one needs to understand "correlations" in various ways, at various levels. This part of Geospatial Intelligibility(different ut linked to geospatial intelligence) has much to do with data mining, with concerns about clustering methods, pattern analysis, geostatistics analysis, multiscale correlations, etc ... Findings with these methods have also some consequences in relation to conflation ("bigger than the sum of its parts"), that is the need of methodologies when either assimilating new datasets in an existing model, or when transposing some information at a a different scale level: changing scale, extrapolations, forecasts. Using multiway statistical methodologies such Principal Tensor Analysis of k-way arrays (see the R add-on package, PTAk ), can be an approach to study some spatio-temporal clustering, multiscale patterns, and spatial co-occurrences at higher orders of marked processes. This can be applied in various domain such as ecology, biogeography, health statistics and spatial epidemiology, where simple modelling and integrated modelling implies the consideration of spatial interaction/association in various aspects. An R add-on package called kOO is underway... Some combination of geospatial geometrical transformations together with attibute spatial analysis can make use fo this framework within the context of generalisation and map schematisation or optimal zoning systems.
in Geoinformatics, Standards & Data Modelling
Interoperability & GeoWorkflows:
the Integrated Modelling research about controlling workflows fits also in the Geoinformatics & Data Modellingtheme. As already mentioned interoperability of data and models allows to build systems which can uses, requests, triggers itself in relation to events (sensors, web 2.0, semantic requests, etc ...). Research on assessing and controlling model workflows is particularly original in addressing the problem of adaptive modelling, when, due to change of context, e.g. new data or model becoming available, precision needed (change of scale), the worklow is dynamically modified in a semi-automated way. In this domain current effort is related to data and meta data/process modelling for workflows and semantic enrichment of workflows in the spirit of semantically driven GIS architectures. This makes use of various XML modelling such as MOML or BPEL, after modelling via SysML and also the BPMN workflow graphical description (which now 2.0 has its own XML, see also the XPDL encoding) . Data Integration, Data Fusion & Data Conflation: In collaboration with my colleagues at the Nottingham Geospatial Institute, an active member of the OGC contributing to various projects at European level linked to FP7, INSPIRE for example. Developing standards and/or contributing to data specifications has some links with the above research. Analysing their pertinence, and performance within implemented architectures for end users is also very much of interests when designing or establishing new uses of existing technologies, and geospatial methods for real case studies.Fusion and Conflation play finer roles, going deeper in the data integration, closer to the the geocomputational use of a collection of semantically related data for a particular application or model represented in a geoworkflow.
see also My Citations
Leibovici, DG. Evans, B. Hodges, C. Wiemann, S. Meek, S. Rosser, J. and Jackson, M. (2015 )On Data Quality Assurance and Conflation Entanglement in Crowdsourcing for Environmental Studies. ISSDQ 2015 - The 9th International Symposium on Spatial Data Quality, 29-30 September, La Grande Motte, France.
Leibovici, DG. Brosset, D. Claramunt, C. and Jackson, M. (2015 ) k-Co-occurrences Density Map Estimation. Spatial Statistics Conference: Emerging Patterns, 9-12th of June 2015, Avignon, France; Procedia Environmental Sciences. 26, 105-€"109.
Stock, K Leibovici, DG. DeLazari, L and Santos, R (2015 ) Discovering Order in Chaos: Using a Heuristic Ontology to Derive Spatio-Temporal Sequences for Cadastral, Roads and Parks Data. Spatial Cognition & Computation, 15(2): 115-141.
Leibovici, DG. Meek, S. Anand, S Santos, R. Morley, J. Jackson, M.J. Al-Azri, M. Mayes, S. Ray, R.Hodgman, C. Baten, A. King, G. Brailsford, T. Vu, T. Karunaratne, A.S. Azman, R. Walker, S. and Azam-Ali, S (2015) Geospatial binding for transdiciplinary research in crop science: the GRASP-GFS initiative (Geospatial Resource for Agricultural Species, pests and Pathogens with integrated workflow modelling to support Global Food Security). In: Integration of Geographic Information Systems into Agro-Environmental Sustainability, Amvridis, A and Ifadis, I (eds), Advances in Geospatial Technologies (AGT) Book Series, IGI-Global (proposal of a chapter accepted)
Hodges, CJ. Leibovici, DG. and Ties, SF. (2014) Building confidence in crowdsourced data for biological monitoring and policy making as part of FP7 Project COBWEB. GIScience 2014, Eight International Conference on Geographical Information Science, Vienna 23-26 September
Huynh ChI, D. Vu, T. Jackson, M. Leibovici, DG. and Mayes, S. (2014) Towards a User-Centric Approach for Assessing Quality of Crowd-Sourced Data, an Application in Agriculture. Role of Volunteered Geographic Information in Advancing Science: Effective Utilization: Workshop GIScience 2014, Eight International Conference on Geographical Information Science, Vienna 23-26 September
Leibovici, DG. Daras, K. and A.G.D Turner (2014) Competing Spatial Optimisation using the k-spatial entropy. . GIScience 2014, Eight International Conference on Geographical Information Science, Vienna 23-24 September
Leibovici, DG. Meek, S. Anand, S Santos, R. Morley, J. Jackson, M.J. Al-Azri, M. Mayes, S. Ray, R.Hodgman, C. Baten, A. King, G. Brailsford, T. Vu, T. Karunaratne, A.S. Azman, R. Walker, S. and Azam-Ali, S (2014) The GRASP initiative, Geospatial Resource for Agricultural Species, pests and Pathogens with integrated workflow modelling to support Global Food Security. In: AgriGIS workshop, â€˜â€™Open Source and Open Data in Crop Modelling and Related Agriculture Issues, OSGIS 2014, 2-3 September 2014, Nottingham, UK
Jackson, M Meek, S Leibovici, DG (2014) NSDI data enhancement through crowdsourcing: the role of quality assurance to ensure effective conflation of authoritative and non-authoritative data sources. INSPIRE conference,Aalborg University, Denmark, 16th-20th June 2014
Meek, S Jackson, M Leibovici, DG (2014) ) A flexible framework for assessing the quality of crowdsourced data.AGILE conference, 3-6 June 2014, Castellon, Spain
Leibovici, DG. Birkin, MH (2014) On Geocomputational Determinants of Entropic Variations for Urban Dynamic Studies. Geographical Analysis. early view 31 Aug 2014
Leibovici, DG. Claramunt, C. Le Guyader, D. and Brosset, D. (2014) Local and global spatio-temporal entropy indices based on distance-ratios and co-occurrences distributions. International journal of Geographical Information, 28(5): 1061-1084
Samarasundera, E. Hansell, A. Anand.S Leibovici, DG. Oppenheimer, C. and Horwell, C. (2014) Geological Hazards: from Early Warnings Systems to Public Health Toollkits. Health & Place, (30): 116-€"119
Leibovici, DG. Birkin, MH (2013) Simple, multiple and multiway correspondence analysis applied to spatial census-based population microsimulation studies using R. NCRM Working Paper. NCRM-n°07/13, Id-3178
Leibovici, DG and Stock K (2013) "Away from data storage complexity, closer to geocomputational data mash-up". COSIT Workshop "Spatio-temporal theories and research for environmental, urban and social sciences: where do we stand?", Panel Discussion ("Needs and Perspectives for Spatio-Temporal Theories"), 2nd of September 2013, Scarborough, UK. (COSIT 2013)
Stock, K and Leibovici, DG (2013) Discovering Order in Chaos by Deriving Spatio-Temporal Data on the Fly. COSIT Workshop "Spatio-temporal theories and research for environmental, urban and social sciences: where do we stand?" 2nd of September 2013, Scarborough, UK. (COSIT 2013)
Leibovici, DG. and Jackson, MJ. (2013) Copula metadata est. AGILE conference, 14-17 May 2013, Leuven, Belgium.(pdf)
Leibovici, DG. Pourabdollah A. and Jackson, MJ. (2013) Which Spatial Data Quality can be meta-propagated? Journal of Spatial Sciences, 58(1): 3-14
Leibovici, DG.Birkin, MH (2012) Entropic variations of urban dynamics at different spatio-temporal scales: geocomputational perspectives. NARSC-RSAI November 2012, Ottawa, Canada
Leibovici, DGPourabdollah, A and Jackson, M (2012) On Interoperability and Web Processing Service setting for Geo- Workflow Quality Assessment and Execution OSGIS 2012, Nottingham, U.K. September 2012
Du, H.Anand, S. Alechina, N. Morley, J. Hart, G. Leibovici, DG. Jackson, MJ. and War, M. (2012) Geospatial Information Integration for Authoritative and Crowd Sourced Road Vector Data. Transactions in GIS, 16(4): 455-476
Pourabdollah A.Leibovici, D.G. Simms, D.M. Piet, T Hallett, S.H. and Jackson M.J. (2012) " Towards a Standard for Soil and Terrain Data Exchange: SoTerML." Computers & Geosciences,45: 270-283 (see also OGC/gml profile application)
Leibovici, D.G.Pourabdollah A. and Jackson M.(2011) " Which Spatial Quality can be Meta-Propagated?" ISSDQ 2011, International Symposium on Spatial Data Quality, 2011, 12-14 October 2011 Portugal
Pawlowicz, SLeibovici, DG Heines-Young, R Saull, R and Jackson, M (2011) " Dynamical Surveying Adjustments for Crowd-sourced Data Observations." EnviroInfo 2011 Ispra, Italy October 2011
Leibovici, D.G.Swan, J. Anand, S. and Jackson M.(2011) " Coupling Outbreak Detection of Spatially Clustered Associations and Data Reduction" STDM-11 (Spatio-Temporal Data Mining), London 18-19 July 2011
Pourabdollah A.Leibovici, D.G and Jackson M.(2011) " MetaPunT: an Open Source tool for Meta-Propagation of uncerTainties in Geospatial Processing." OSGIS 2011, Nottingham 21-22 June, 2011
Leibovici, D.G.Pourabdollah A. and Jackson M.(2011) " Meta-propagation of Uncertainties for Scientific Workflow Management in Interoperable Spatial Data Infrastructures" EGU 2011, European Geosciences Union, General Assembly, Vienna, Austria April 2011
Leibovici, D.G.Bastin, L. Anand, S. Hobona, G. and Jackson, M (2011) " Spatially Clustered Associations in Health related geospatial data". Transactions in GIS, 15(3): 347-364 (June-July 2011)
Leibovici, D.G.and Jackson, M. (2011) " Multi-scale Integration for Spatio-Temporal Ecoregioning Delineation." International Journal of Image and Data Fusion, 2(2): 105-119
Leibovici DG, .Bastin L,. and Jackson M. (2011) " Higher-Order Co-occurrences for Exploratory Point Pattern Analysis and Decision Tree Clustering on Spatial Data." Computers & Geosciences: 37(3): 382-389