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Time for a new Tandem?. Marja Tammilehto-Luode. Time for a new Tandem Reflections of the study about grids and blobs. Tandem studies - Tandem I - content and conclusions Tandem II - content and conclusions Results and next step. Tandem studies. a joint initiative by NSIs (ONS,SF,SS)
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Time for a new Tandem? Marja Tammilehto-Luode
Time for a new TandemReflections of the study about grids and blobs • Tandem studies - • Tandem I - content and conclusions • Tandem II - content and conclusions • Results and next step Marja Tammilehto-Luode
Tandem studies • a joint initiative by NSIs (ONS,SF,SS) • ”In search for a common Geographical Base to compare Statistics across the EU” • cooperative action carried out in 2000-2003 • funded by a grant from the Commission (85%) • Tandem I 2000-2002, three parties, individual grants Tandem II 2002-2003, three parties a joint grant • Tandem I, ?Tandem II, 15 staff months according to work plan Marja Tammilehto-Luode
Tandem IPoint of departure: A need for more comparable territorial divisions for statistics • to visualise data more effectively • to combine and compare data on different spatial units • to combine or compare data on different spatial scales • to make better statistical/spatial analysis of data (to test spatial patterns and trends Marja Tammilehto-Luode
The study of two parallel approaches • Regular tessellation approach • Statistics Finland’s responsibility • study of methods to construct grid-based statistics • tests of candidate methods with empirical data • construction of a prototype • tests on a prototype with a user case • Irregular tessellation approach • Office of National Statistics in UK’s responsibility • study of methods of zoning design • tests with ZDES (Zone Design System) by Leeds University with empirical data • tests on a prototype with a user case Marja Tammilehto-Luode
Regular tessellation Irregular tessellation Input areas Building blocks Output areas Marja Tammilehto-Luode
Tandem I: Work packages • WP1: A Professional context • WP2: A Theoretical Assessment • WP3: A Practical Assessment • WP4: Results and recommendations Marja Tammilehto-Luode
Tandem I: Conclusions • need for methods to optimise intermediate territorial divisions - to make/standardise “building blocks” • need for two parallel approaches - regular tessellation and irregular tessellation approach • harmonised methods for spatial analysis (delineation for example) are as important as comparable data itself • need for special disclosure control methods Marja Tammilehto-Luode
Tandem I - Report • Backer, L. , Tammilehto-Luode, M., Gublin, P. (2002). Tandem GIS _I. A Feasibility study towards a common geographical base for statistics across European Union • Eurostat working papers: Http://europe.eu.int/comm/eurostat/Public/ Marja Tammilehto-Luode
The first report: • http://europa.eu.int/comm/eurostat/Public/datashop/print-catalogue/EN?catalogue=Eurostat&collection=12-Working%20papers%20and%20studies[Theme: General Statistics](Issue Date: 18/09/2002) • PDF -file 154 pages • with pictures 200 pages Marja Tammilehto-Luode
Objectives of Tandem II • Further development of methods introduced in Tandem_GIS I • Test with data of new variables and different kind of georeferences and different scale of analysis • Case studies-to highlight contrasts between geographical areas-to improve clustering methods and production of better estimates-to develop methods to transform data of different territorial divisions Marja Tammilehto-Luode
Tandem II: Content of Action • How to build/a strategy for an SSAS (System of Small Area Statistics) for Europe • Development of delineation methods • Comparison of grid-based and polygon-based approaches in zoning/delineation • Guidelines for dissemination of small area statistics Marja Tammilehto-Luode
Comparable territorial areas Comparable territorial statistics = SSAS Building Blocks or Methods Data Comparable Statistics Grids and Blobs Marja Tammilehto-Luode
A vision of SSAS in the year 2010 • Phase I – Consolidation, Standardisation and Collaborative Research (2004 – 2008)-a common framework for spatial referencing, standard definitions and methods to construct building blocks... • Phase II – Dissemination and Local implementation (2006 – 2010-recommendations, guidelines available • Phase III – SSAS (2010 - ), -a catalogue of SSAS, easy-to use tools, documented user cases, recommended methods for spatial analysis Marja Tammilehto-Luode
EU strategy for SSASEurostat guides, intrepreters, investigates Inspire,harmonisation rules Tuning of the strategy Best practices-applying data, features and methods ESPON and others networks Ongoing feedback NSIs and NMAs Marja Tammilehto-Luode
Development of delineation methodsCase studies • WP3: Delineation by Automated Zoning Method (AZM) • WP4: Delineation by Interpolation (Kriging) • WP5: Delineation by AZM and Kriging Marja Tammilehto-Luode
AZM (ZDES, University of Newcastle, UK) Area-based input data Area optimisation by certain criteria Creates comparable data by chosen constraints Problems - Computing time- Islands- Definition of number of output areas Kriging (Surfer, ArcGIS…) Point-based input data Creates continuous surface by predicting cell values Isolines of certain values for delineation Problems- Several interpolation methods available - may give different results- Dependent on coverage of data Comparison of AZM and Kriging Marja Tammilehto-Luode
Grid-based approach Best with accurate data (total coverage), otherwise estimation needed Spatial, comparable building blocks AZM, Kriging and classification applicable Applicable to different scales and resolutions Polygon-based data Small area statistics (smaller than NUTS5) - otherwise spatial analysis not valuable AZM - when boundaries known (low resolution) Kriging when boundaries unknown (low to high resolution) Building blocks could be optimised first by AZM Comparison of grid-based and polygon-based approaches Marja Tammilehto-Luode
Guidelines for dissemination of small area statisticsInternational/European.. • Harmonised data- Need for reference data- Focus on metadata- Standard data model, storage format, output format- Common gridnet • Collaborative agreement- Formal project with proper funds- Focus on harmonised data specifications and common standards- Co-operation with mapping authorities may be fruitful- Third party may be needed to facilitate and optimise sharing, trading and extensive use of multinational data Marja Tammilehto-Luode
Guidelines for dissemination of small area statistics • Quality and disclosure control- Different practice in each country- Essential part of good statistics- Emerging international standards (ISO 11913-11915)- Requires further studies/research both nationally and internationally- High expectations on INSPIRE • National and/or international guidelines- International guidelines can never compensate national standards- National guidelines should adopt international concepts, definitions, classifications, metadata descriptions…. Marja Tammilehto-Luode
Guidelines for dissemination of small area statistics • International - standardised grid net necessary- Common origo- Proper projections for different scales - For joining data from different areas (horizontally)- For joining data from different data sources (vertically)- For data capture, spatial analysis • International guidelines to enable better access to data Marja Tammilehto-Luode
Conclusions • SSAS - Framework of spatial data of NSIs needed • Harmonisation with ESDI and INSPIRE with emphasis on analytical information • Top-down co-ordination - Bottom-up implementation • Restructuring and refinement of current systems • Focus on user needs and case studies • Standards for Data, Features and Methods • Scalability, comparability, delineation, confidentiality, quality, easy-to-use procedures... Marja Tammilehto-Luode
Conclusions • SSAS - Framework of spatial data of NSIs needed • Harmonisation with ESDI and INSPIRE with emphasis on analytical information • Top-down co-ordination - Bottom-up implementation • Restructuring and refinement of current systems • Focus on user needs and case studies • Standards for Data, Features and Methods • Scalability, comparability, delineation, confidentiality, quality, easy-to-use procedures... Marja Tammilehto-Luode
Tandem II - Report • Tandem II: • Tammilehto-Luode, M., Ralphs, M., Backer, L. (2003). Tandem II. Towards a common geographical base for statistics across Europe. The final report. 25 pages + Appendices 256 pages. Marja Tammilehto-Luode
ResultsBetter understanding of spatial statistics • traditional regional statistics cannot describe properly regional changes of distribution of welfare-example of BKT/inhabitants of London • more precise allocation of multi problematic areas may cause better follow up of potential actions • more precise allocation of social actions may save governmental spending • small building blocks for other/flexible territorial statistics • solutions for regional timeseries • use of spatial analysis • INSPIRE Marja Tammilehto-Luode
Results • Long term general strategy to build SSAS (a system of small area statistics) for Europe • Development of delineation methods • Comparison of grid-based and polygon-based approach in zooning /delineating • Guidelines for dissemination of small area statistics Marja Tammilehto-Luode
Results • a proposal for a Eurogrid - a software to make it • prototype of population grid data, a hierarchy of grids - by aggregation and disaggregation methods • European gridclub - number of members growing(?) • several references (citations) in other publications - many focusing the census 2010 Marja Tammilehto-Luode
GEOSTAT? Marja Tammilehto-Luode