Transcript Geert Bruinooge, Deputy Director General, Statistics Netherlands

Counting the Dutch, The
Future of the Virtual
Census in the Netherlands
Presentation at the seminar
Counting the 7 Billion
24 February 2012
*
Geert Bruinooge
*
[email protected]
Contents
• History of the Dutch Census
Traditional and virtual Censuses
• Registers and surveys
Strategy: order of data collection, system of basic registrations,
basic registration stakeholders, challenges in surveys
• Virtual Census
Introduction to virtual census, definition and driving forces of the
SSD, combining sources: micro linkage, conditions facilitating
use of administrative sources,advantages and disadvantages
1
History of the Dutch Census (1)
TRADITIONAL CENSUS
Ministry of Home Affairs:
1829, 1839, 1849, 1859, 1869, 1879 and 1889
Statistics Netherlands:
1899, 1909, 1920, 1930, 1947, 1960 and 1971
Main problem: unwillingness (nonresponse)
Additional problem: reduction of expenses
 no more Traditional Censuses
2
History of the Dutch Census (2)
ALTERNATIVE: VIRTUAL CENSUS
1981 and 1991: Population Register and surveys
Development 90’s: more registers →
2001 and 2011:
Virtual Census: integrated set of registers and surveys
Social Statistical Database (SSD)
2001: Gentlemen’s agreement (with Eurostat)
2011: European Census Act
3
Registers and surveys (1)
Strategy: order of data collection
1. Secondary sources
 where possible (total or partial replacement)
 Statistics Netherlands has free access to all
governmental data
2. Primary sources
1. Electronic/internet
2. Paper
3. Telephone
4. Face-to-face
4
Registers and surveys (2)
System of linked and unique basic registrations
•
•
•
•
•
•
•
•
•
population (residents and non-residents)
buildings and addresses
enterprises (e.g. number of employees)
real estates (boundaries, ownership, value, ..)
topography (maps: land, water, roads)
motor cars (model, colour, ownership, ..)
taxable income (e.g. fiscal wage)
labour (wage, employer, ..)
subsoil (sewerage, cables, ..)
5
Registers and surveys (3)
Basic registrations stakeholders
Features of basic registrations
• Based on legislations. Cabinet ministers are
responsible for registrations. The Minister for the
Interior is responsible for the system as a whole.
• Basic data are kept in only one register. Public sector
organizations (ministries, tax authorities, local social
welfare, …) are not allowed to collect and keep
similar data.
Stakeholders
• the cabinet minister (+ civil service)
• the keeper(s) of the registration
• the users (example: Statistics Netherlands)
6
Registers and surveys (4)
Challenges in surveys
• Optimizing capacity (interviewers / agents)
• Contract management (CAPI / CATI)
• Home based interviewing
• Optimizing the use of different collection modes
(mixed mode) with respect to
• Response rates
• Collection costs (capacity needed)
• Decreasing availability telephone numbers
• Special approach for difficult to reach groups
because of low response rates
7
Virtual Census (1)
Introduction
Why a Census?
Statistical information for research and policy purposes
What kind of information?
• Size of (sub)population(s), excluding illegal people (homeless are
counted at last known address, special survey: catch-recatch method)
• Demographic and socio-economic characteristics, at
national and regional level (frequency tables → small confidentiality
problems
Current situation
• Eurostat: coordinator of EU, accession and EFTA
countries in the 2011 Census Round
• Census Table Programme, every 10 years
8
Virtual Census (2)
Definition and driving forces of the SSD
Definition:
set of integrated microdata files with coherent and detailed
demographic and socio-economic data on persons,
households, jobs and benefits
After edit process: only coherent information
Driving forces:
• Virtual Census of 2001
• Better products: more coherence and flexibility
9
Virtual Census (3)
Combining sources: micro linkage
• Linkage key:
Registers
Citizen Service Number, unique
Surveys
Sex, date of birth,
address (postal code and house number)
• Linkage key replaced by Record Identification Number of
the person (because of confidentiality)
• Linkage strategy
Optimizing number of matches
Minimizing number of mismatches and missed matches
10
Virtual Census (4)
Conditions facilitating use of administrative
sources
• Legal base (Statistics Act)
• Public approval (‘Big Brother is watching you’)
• Cooperation among authorities (mainly government
organisations)
• Comprehensive and reliable register system
(administrative versus statistical quality)
• Unified identification system (preferably unique IDnumbers)
11
Virtual Census (5)
Advantages
• Relatively cheap (small cost per inhabitant: 1% of a
traditional census)
• Quick (short production time)
• Less problems with non-response
• Annual updates are no longer necessary:
Census data are continuously available!
12
Virtual Census (6)
Disadvantages
• Concepts and population of registers may differ from
what is needed (keep good relations with the
register holders!)
• Publication of small subpopulations sometimes
difficult or even impossible because of limited
information in already existing surveys (e.g.
occupation, level of education)
• How to keep knowledge and IT infrastructure up-todate for a process that is running only every ten
years?
• Attention for the Census (results) diminishes
13
14