The effect of changing regional classifications on statistical indicators October 2008, Shanghai Dr. Udo Maack Germany SCORUS Conference 2008

Changing Regional Classifications 1.The role and characteristics of regional statistical indicators 2.What happens when regional classification changes? 3.Provisions to avoid a false reporting? Recalculation procedure Regional Classification Server (structure and products)

1. The role and characteristics of regional statistical indicators  Describe real world phenomena  Measure developments in time series  Compare between regions of … – one country – different countries (international)  Values must be normalized e.g. using area or population or (…)

2. What happens when regional classification changes?

Which changes may occur? (I) Number of Provinces in Turkey between 1990 ( Census) and Census

Which changes may occur? (II)

3. Provisions to avoid a false reporting? (1) Provide a centrally maintained Regional Classification Server (RCS) (2) Recalculate values and indicators (3) Force the use of the newest classification on all production steps

Role of a central Regional Classification Server Report B Report A GeoCoding Statistical Production Process A (Population) Central RCS spatial analysis comparison, combination Statistical Production Process B (Hospital) Feedback / Recalculation / Recalculation

Role of a central Regional Classification Server External Data Production Regional Statistics DB RCS Manually prepared Uploading Internal Data Production Meta Database

Solution for the Turkish National Statistical Office TURKSTAT (under development) External Data Provider Regional Statistics DB Address DB RCS Quality assured Workflow for Uploading Data Production Meta Database National Address DB

Recalculation of Values and Indicators Basic - Values If surveyed / reported values are available, these values have to be aggregated from the original level to regional units according the new territorial division Indicators must be calculated again from the basis values on all regional level not available, the existing values have to be recalculated using weighting factors – of other sources, if available preferred – derived from change of area or population, which have to be provided in the RCS

Results of the recalculation of values

Basic structure of a RCS (I) Standard Information: description of regional units with lifetime Area Population ToFrom IdentifierName timeLifeUnit

Basic structure of a RCS (I) Example

Basic structure of a RCS (II) Example Date of change From- Unit To- Unit AreaPopula- tion Required extension: Change information

Basic structure of a RCS (II) Example

Products of the RCS (I) Status Table Conc-Moda*) Table [EU required] Correspondence Table *) Conc-Moda: ………………….

Products of the RCS (II) Status Table

Products of the RCS (III) Conc-Moda Table

Products of the RCS (IV) Conc-Moda Table

Products of the RC (V) Correspondence Table

Recalculation of values

Summary The influence of regional changes is significant to statistical values (time series) Retrograde data should be adjusted to provide comparable data Provisions on data and methods Regional Classification Server Force all producers to use the RC-Server

Changing regional classifications Acknowledgements: TURKSTAT (National Statistical Office of Turkey) Ms. MelikeYildirim Head of Department Publication and Data Dissemination USST-Project ( U pgrading the S tatistical S ystem of T urkey; EU-Aid Project) Mr. Ullrich Eichler Head of the Project Implementation Team

Thank You Dr. Udo Maack, Berlin, Germany Phone: Changing regional classifications ?