Transcript Register-Based Census 2011 in Slovenia – Some Quality Aspects Danilo Dolenc Statistical Office of the Republic of Slovenia UNECE-Eurostat Expert Group Meeting on Censuses Using Registers,

Register-Based Census
2011 in Slovenia – Some
Quality Aspects
Danilo Dolenc
Statistical Office of the Republic of Slovenia
UNECE-Eurostat Expert Group Meeting on Censuses Using
Registers, Geneva, 22-23 May 2012
Basic facts (1)
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Fully register-based census using data from
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Administrative registers (5)
Statistical register (1)
Administrative databases (7)
Statistical surveys (full coverage) (6)
Organized as a project
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Started in 2009
Project team consists of 6 employees
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No permanent staff
No outsourcing
No budget (savings around 14 mio EUR)
Census considered as regular statistical survey
Basic facts (2)
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Reference date 1 January 2011
Three (four) stages of the statistical process
following the availability of sources concluded by
dissemination of data:
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Basic demographic data (30 April 2011)
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Produced quarterly
Households and families (30 June 2011)
Other population topics (30 December 2011)
 Including occupied dwellings – preliminary data
Housing (by the end of June 2012)
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Delay due to the updated version of administrative data (Real
Estate Register)
Background
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Four basic registers set up by SORS far ago
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CPR for the first time used for statistics in 1986
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Register of Spatial Units (address list) in 80‘s
Statistical Register on Employment – from 1986
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In 2002 data on occupation, industry, place of work taken over
Business Register in 1976
Two missing registers available after 2002
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Data already used in 1991 and 2002 Censuses
Real Estate Register established in 2007
Household Register computerized
CPR supplemented with dwellings number
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Mini project of SORS and Ministry of Interior in 2010
Preparatory phase (1)
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Analyses and evaluation
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Data sources
Quality of data
Methodological and processing solutions
Trial census carried out in 2010 - main findings
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Inconsistencies in Household Register
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Easy to improve quality
Solved by Ministry of the Interior on the basis of SORS
guidelines
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Detected errors should be corrected in primary source
Preparatory phase (2)
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Missing dwelling numbers (DN) in CPR
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More than half of population living in multi-dwelling
buildings
Two main activities for improvement undertaken
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Automated determination of DN on the basis of ownership
and residence
49,000 letters sent to residents without DN
– Response rate 75 % including returning letters by post
Still 12.3 % of missing DN in input database
Preparatory phase (3)
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Unsatisfactory quality of Real Estate Register
data
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The main problem in whole statistical process
SORS analyses sent to register keeper
Public data – owners had chance to check and change
data
Data on ownership depends on long-lasting legal
matters
Re-updating of final database – selected topics
Linkage of data (1)
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Identifiers crucial for integration of persons,
households and dwellings
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PIN (transformed to SID before the process)
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Household number
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Housekeeping concept is implemented
Not available for foreigners - 2.1% HN missing
Relation to the reference person could be considered as identifier
(key for family generation)
Dwelling number
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Basic identifier for most of linkage regarding persons
The share of missing data still high – 12.3%
Address
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Unique identifier of every building
Linkage of data (2)
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Statistical process almost completely automated
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Very complex rules for imputing key identifiers
Interface for manual editing incorporated in the
statistical process
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Better quality – but only 1% records
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Household formation of foreigners
Family formation
– Multi-member households
– Households without data on biological parents or spouses
Quality indicators - identifiers
Number
of
records
724,479
75.3
Imputed
Automated
Manual
Share in %
11.7
0.6
2,016,423
94.9
2.0
0.1
2.3
0.6
Relation to the
2,016,423
2)
reference person
91.6
4.1
0.1
3.3
0.83)
Identifier
Dwelling ID1)
Household ID2)
1)
Unchanged
Multi-dwelling buildings only.
Private households only.
3)
Manual corrections in the stage of family generation also included.
2)
Corrections
Automated
Manual
11.9
0.5
Current activity status
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Population aged 15+
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Data integration stage
Priority Source content
1
2
3
4
5
6
7
8
Employed persns
Registered unemployed persons
Students enrolment
Scholarship resipients
Recipients of pensions
Health insured persons
Recipients of social benefits
Income tax payers
Period
24-31.12. 2010
1.1.2011
2010/2011
1.1.2011
1.1.2011
1.1.2011
2010
2010
Number of records
Input
Output
820.793
109.994
91.654
31.076
582.594
1.253.284
94.812
1.619.247
804.854
104.560
77.346
18.353
511.279
187.418
14.455
10.124
Share %
98,1
95,1
84,4
59,1
87,8
15,0
15,2
0,6
Imputation
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Almost all missing data imputed
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Two main methods used
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Except occupation, industry and status in employment for
persons working abroad (e. g. daily commuters)
Automated corrections on the basis of existing correlated
data (e.g. activity status by health insurance code)
Hot-deck imputation
Imputation rates – lower than in 2002 Census
Activity status
Occupation (employed)
Industry (employed)
Place of work
1.5% Occupation (unemployed) 5.2%
3.9% Industry (unemployed)
18.0%
3.7%
3.8% Educational attainment
1.5%
Where should we be heading ?
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Integration into social statistics
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Coverage
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Census data used for regular surveys (e.g. country ob
birth of parents, immigrant background)
Cooperation with MI to improve over-registration
Geo-referencing
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Free of charge on the web – application KASPeR
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Qualty of processes and outputs
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Every single change of data from the input databases to
the final census database is recorded
 Introducing manual interface for improving quality
Common tools – internal integration of IT processes
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Over-registration
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Common problem of register-based systems
Missing data on activity status used as indicator
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Data from 8 sources used
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Overestimated population groups
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For 1,25 % of population no evidence in any source
Foreigners with permanent residence
Working age population (30-44 years) – working abroad?
Administrative survivors (over 94 years)
Final estimation 0.9%
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Very comparable with households surveys
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No need for post-enumeration survey
Conclusion
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Two main conditions for input data quality
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Close cooperation with register keepers
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Permanent use of registers
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Not only for statistical purposes
In future no more ‘‘Census‘‘ but regular
annual/periodical survey
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Feedback implemented in primary source
Every 3-4 years complete ‘‘Census‘‘
Every year education, activity, migration data
Twice a year basic demographic data including
citizenship
New term instead of ‘‘Census‘‘ ???
Thank you for your attention!