Time for a new Tandem? Marja Tammilehto-Luode. Bled 20082Marja Tammilehto-Luode Time for a new Tandem Reflections of the study about grids and blobs Tandem

Time for a new Tandem?

Marja Tammilehto-Luode

Bled 2008 2Marja 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


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


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

m

The Tandem Consortium


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

The Tandem Consortium


Input areas

Building blocks

Output areas

Regular tessellation Irregular tessellation




Tandem I: Work packages

WP1: A Professional context WP2: A Theoretical Assessment WP3: A Practical Assessment WP4: Results and recommendations


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


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/


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


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


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


Building Blocks or Methods

Data

Grids and Blobs

Comparable Statistics

Comparable territorial areas

Comparable territorial statistics

= SSAS


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


EU strategy for SSASEurostat guides, intrepreters,

investigates

NSIs and NMAs

Best practices-applying data,

features and methods

ESPON and others

networks

Inspire,harmonisation rules

Ongoing feedback

Tuning of the strategy


Development of delineation methodsCase studies

WP3: Delineation by Automated Zoning Method (AZM)

WP4: Delineation by Interpolation (Kriging)

WP5: Delineation by AZM and Kriging


Comparison of AZM and Kriging

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 grid-based and polygon-based approaches

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


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 grid net 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


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….


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






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...


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...


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.



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


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


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



GEOSTAT?

Documents

Time for a new Tandem? Marja Tammilehto-Luode. Bled 20082Marja Tammilehto-Luode Time for a new Tandem Reflections of the study about grids and blobs Tandem