Census Mapping & the use of
Geo-Spatial Technologies
(South Africa)
United Nations Expert Group Meeting, New York,
29 May – 1 June 2007
Sharthi Laldaparsad
Executive Manager, Geography Division, Statistics South Africa
Sharthil@statssa.gov.za
Contents:
1. The PAST
2. The PRESENT
3. The FUTURE
The learning's from each…
The PAST
Census
1996
&
prior
Census
1996
&
prior
Census
1996
&
prior
Post Census 1996
•
•
•
•
Approached by Electoral Commission
Financial sponsor
Joint project (called Project EAgle)
4 Government Departments (Electoral
Commission, Land Affairs, Demarcation Board,
Stats SA – nicknamed the BIG FOUR)
Census 1996 Dissemination
• By 1998, SA had its first digital set of EAs
• Stats SA used for Census 1996 products
(using SuperCross)
• Aggregated into small-areas. (Place names)
Census 2001
•
•
•
•
1996 digital data as a basis
Started building core infrastructure – GIS Section
Joint partnerships to acquire photography
80-90% of the 2001 Census EAs demarcated
from photography, 10% field inspection
• Intensive in-house map production (400 000 A3 maps)
• Map reading & interpretation training for census
publicity & enumeration
•
•
Dissemination (Supercross, Digital Spatial CD)
Data confidentiality: Dissemination layer, small area
layer.
Learning’s from the PAST
• Census Mapping is a core responsibility for a
statistical agency so “grow your own timber”.
• Move from census-centric to corporate-centric.
(The GEOGRAPHY DIVISION was created.)
• Maintain a Standard Geographic Frame
• Address the un-addressed (The ADDRESS Project
started)
The PRESENT
System
of Statistics
National Accounts
ECONOMIC
GROWTH
Strategically
positioning
Geography
in a
Statistical
organisation
Industry and Trade Statistics
Primary sector statistics
Agriculture statistics
Secondary sector statistics
Tertiary sector statistics
Tourism statistics
Business services statistics
Annual supply & use tables
Satellite accounts
Social Statistics
General household survey
Second economy information
Master sample
User paid surveys
Financial statistics
National Government Accounts statistics
Provincial Government Accounts statistics
Local Government Accounts statistics
Non-financial Local Government statistics
Private sector statistics
Vital Statistics
Birth, death, health, marriage &
divorce statistics
Tourism statistics
Migration statistics
Employment Statistics
Quarterly employment survey
Labour force survey
Population Statistics
Price Statistics
Consumer price index (CPI)
Rural consumer price index
Production price index (PPI)
Business Frame
Population Census
Community Survey
Thematic reports on demographic
processes,
fertility, health, ageing and mortality
Population projections and estimates
Geographic Frame
Methodology and Standards
SOCIAL
DEVELOPMENT
Quarterly and annual gross domestic product estimates
Benchmarking gross domestic product estimates
GEOGRAPHY DIVISION provides
the relevant geographic infrastructure for data
collections, processing, analysis & dissemination
Geographic infrastructure includes:
• Geographic Systems
• Geographic Methods
• Geographic Standards
‘Geographic knowledge’
Input
Output
Statistical process
4
Outcome
5
3
2
1
People
management
Data items
Questionnaire
design
Sample
design
Programming
Quality plan
and criteria
Collect
Process
Postal survey
Quality check
Household
survey
Administrative
records/
Government
MIS
Classification
Capture
Edit
Analyse
Publication
Analyse
data quality
Estimation
Tabulation
Compile
statistical
release/report
Quality audit certification
Editing and
layout
Information
management &
environment
Finance and
Resource
management
Disseminate
Publication
on the web
Distribution
via post
Distribution
of metadata CD
Special
requests
Impact on:
Trade & Industry
Labour statistics
Price statistics
Financial
statistics
Social statistics
Population
statistics
Standards and definitions
Classification systems
Vital statistics
Geographic frame/Business Frame
Poverty
statistics
Data management information delivery
National Accounts
Leadership
Business and
Operational
planning
Survey
planning
Integrative economic,
social and demographic
information
Strategy
Customer focus
Poverty
alleviation
Access to basic
services
Emerging and reemerging diseases
Rural
development
Economic growth
Job creation
Tourism
Governance
Environment
SADC/NEPAD
Other official statistics (NSS)
Statistics South Africa’s VALUE CHAIN
Input
Output
Statistical process
4
Outcome
5
3
2
1
People
management
Data items
Questionnaire
design
Sample
design
Programming
Quality plan
and criteria
Collect
Process
Postal survey
Quality check
Household
survey
Administrative
records/
Government
MIS
Classification
Capture
Edit
Analyse
Analyse
data quality
Estimation
Tabulation
Information
management &
environment
Finance and
Resource
management
Publication
Compile
statistical
release/report
Quality audit certification
Editing and
layout
Disseminate
Publication
on the web
Distribution
via post
Distribution
of metadata CD
Special
requests
Impact on:
Trade & Industry
Labour statistics
Price statistics
Financial
statistics
Social statistics
Population
statistics
Standards and definitions
Vital statistics
National Accounts
Leadership
Business and
Operational
planning
Survey
planning
Integrative economic,
social and demographic
information
Strategy
Poverty
alleviation
Access to basic
services
Emerging and reemerging diseases
Rural
development
Economic growth
Job creation
Tourism
Analysis for proper
geographic
Geographic
frame/Business Frame representation
Povertyof samples
Environment
statistics
Data management information delivery
Maps
for sample units
SADC/NEPAD
Customer
focus
Other official statistics (NSS)
Map reading training
Classification systems
Governance
Input
Output
Statistical process
4
Outcome
5
3
2
1
People
management
Data items
Questionnaire
design
Sample
design
Programming
Quality plan
and criteria
Collect
Process
Postal survey
Quality check
Household
survey
Administrative
records/
Government
MIS
Classification
Capture
Edit
Analyse
Publication
Analyse
data quality
Estimation
Tabulation
Compile
statistical
release/report
Quality audit certification
Editing and
layout
Information
management &
environment
Disseminate
Publication
on the web
Distribution
via post
Distribution
of metadata CD
Special
requests
Impact on:
Trade & Industry
Labour statistics
Price statistics
Financial
statistics
Social statistics
Population
statistics
National Accounts
Leadership
Business and
Operational
planning
Survey
planning
Integrative economic,
social and demographic
information
Strategy
Maps for field work collection
Management information for monitoring collection
Customer focus
Direct digital data collection
Finance and
Resource
management
Standards and definitions
Classification systems
Vital statistics
Geographic frame/Business Frame
Poverty
statistics
Data management information delivery
Other official statistics (NSS)
Poverty
alleviation
Access to basic
services
Emerging and reemerging diseases
Rural
development
Economic growth
Job creation
Tourism
Governance
Environment
SADC/NEPAD
Input
Output
Statistical process
4
Outcome
5
3
2
1
People
management
Data items
Questionnaire
design
Sample
design
Programming
Quality plan
and criteria
Collect
Process
Postal survey
Quality check
Household
survey
Administrative
records/
Government
MIS
Classification
Capture
Edit
Analyse
Publication
Analyse
data quality
Estimation
Tabulation
Compile
statistical
release/report
Quality audit certification
Editing and
layout
Information
management &
environment
Disseminate
Publication
on the web
Distribution
via post
Distribution
of metadata CD
Special
requests
Impact on:
Trade & Industry
Labour statistics
Price statistics
Financial
statistics
Social statistics
Population
statistics
Link data to locations in capturing process
Direct digital capture
Customer focus
Quality assurance
Finance and
Resource
management
Standards and definitions
Classification systems
Vital statistics
Geographic frame/Business Frame
Poverty
statistics
Data management information delivery
National Accounts
Leadership
Business and
Operational
planning
Survey
planning
Integrative economic,
social and demographic
information
Strategy
Other official statistics (NSS)
Poverty
alleviation
Access to basic
services
Emerging and reemerging diseases
Rural
development
Economic growth
Job creation
Tourism
Governance
Environment
SADC/NEPAD
Input
Output
Statistical process
4
Outcome
5
3
2
1
People
management
Data items
Questionnaire
design
Sample
design
Programming
Quality plan
and criteria
Collect
Process
Postal survey
Quality check
Household
survey
Administrative
records/
Government
MIS
Classification
Capture
Edit
Analyse
Publication
Analyse
data quality
Estimation
Tabulation
Compile
statistical
release/report
Quality audit certification
Editing and
layout
Information
management &
environment
Disseminate
Publication
on the web
Distribution
via post
Distribution
of metadata CD
Special
requests
Impact on:
Trade & Industry
Labour statistics
Price statistics
Financial
statistics
Social statistics
Population
statistics
The integrating power of geography
Spatial analysis
Finance and
Resource
management
Standards and definitions
Classification systems
Vital statistics
Geographic frame/Business Frame
Poverty
statistics
Data management information delivery
National Accounts
Leadership
Business and
Operational
planning
Survey
planning
Integrative economic,
social and demographic
information
Strategy
Customer focus
Other official statistics (NSS)
Poverty
alleviation
Access to basic
services
Emerging and reemerging diseases
Rural
development
Economic growth
Job creation
Tourism
Governance
Environment
SADC/NEPAD
Input
Output
Statistical process
4
Outcome
5
3
2
1
People
management
Data items
Questionnaire
design
Sample
design
Programming
Quality plan
and criteria
Collect
Process
Postal survey
Quality check
Household
survey
Administrative
records/
Government
MIS
Classification
Capture
Edit
Analyse
Publication
Analyse
data quality
Estimation
Tabulation
Compile
statistical
release/report
Quality audit certification
Editing and
layout
Information
management &
environment
Finance and
Resource
management
Publication
on the web
Distribution
via post
Distribution
of metadata CD
Special
requests
Impact on:
Trade & Industry
Labour statistics
Price statistics
Financial
statistics
Social statistics
Population
statistics
Standards and definitions
Spatial products
To aid interpretation
Classification systems
Vital statistics
Geographic frame/Business Frame
Poverty
statistics
Data management information delivery
Customer focus
Disseminate
National Accounts
Leadership
Business and
Operational
planning
Survey
planning
Integrative economic,
social and demographic
information
Strategy
Poverty
alleviation
Access to basic
services
Emerging and reemerging diseases
Rural
development
Economic growth
Job creation
Tourism
Governance
Environment
SADC/NEPAD
Other official statistics (NSS)
Input
Output
Statistical process
4
Outcome
5
3
2
1
People
management
Data items
Questionnaire
design
Sample
design
Programming
Quality plan
and criteria
Collect
Process
Postal survey
Quality check
Household
survey
Administrative
records/
Government
MIS
Classification
Capture
Edit
Analyse
Publication
Analyse
data quality
Estimation
Tabulation
Compile
statistical
release/report
Quality audit certification
Editing and
layout
Information
management &
environment
Disseminate
Publication
on the web
Distribution
via post
Distribution
of metadata CD
Special
requests
Impact on:
Trade & Industry
Labour statistics
Price statistics
Financial
statistics
Social statistics
Population
statistics
Standards and definitions
National Accounts
Leadership
Business and
Operational
planning
Survey
planning
Integrative economic,
social and demographic
information
Strategy
Enable users to select information relevant
to their place of interest
Finance and
Resource
management
Classification systems
Vital statistics
Geographic frame/Business Frame
Poverty
statistics
Data management information delivery
Customer focus
Other official statistics (NSS)
Poverty
alleviation
Access to basic
services
Emerging and reemerging diseases
Rural
development
Economic growth
Job creation
Tourism
Governance
Environment
SADC/NEPAD
a Geo-Referenced Dwelling Frame
for SA
Geo-referenced Dwelling Frame for RSA
Our benefits

Lower level (lower than EA) frame for conducting censuses and sampling for
surveys. (Frame for all household-based surveys & censuses)

Identification and exact location of sampling unit

Continuously maintained listings

EA demarcation, digital listings, possible replacement for Census of Housing!

Linkages to other administrative systems
Not only Stats SA benefits  Department of Provincial and Local Government
 Department of Land Affairs
 IEC
 Post Office, Telkom
 Department of Home Affairs
 Department of Mineral and Energy (also Eskom)
 Department of Housing
 Department of Health
 Department of Water Affairs
 Department of Social Development
 SITA
 DBSA
 Mix of doers (collect, maintain and update) and users (integration and analysis)
e.g. private companies
Structure
Geo-Referenced Dwelling Frame
Formal Areas and Farms
• Comprises visiting Metropolitan Councils
and other municipalities to obtain existing
address data sets
• Linked to cadastral data from
municipalities
• Currently no data standards
• Little or no capacity for maintenance
Traditional and Informal
areas
• No or limited address information
available
• Conduct fieldwork to obtain data
• Unique identifier versus an address
(i) Creation:
•
•
•
Recording of aerial photography
Capturing of spatial points (office work) on structures
Verification of the captured spatial points in the field,
additions of new dwellings and capturing 18 attributes
(ii) Assign addresses:
•
•
Converting unique identifiers to addresses
Displaying addresses on dwellings
(iii) Maintenance:
•
•
•
Joint maintenance strategy between stakeholders
Recruit & train one person per municipality / DC
Equip municipality with data, hardware & software
•
•
Placement of staff at municipalities
Provide support and monitor continuously
•
(v) Roll out:
Implementation country wide
Methodology
(iv) Applications:
•
•
•
•
•
MIIF
Valuation roll
Project Consolidate
IDP
District Shared Service sites
•
•
•
Community Survey 2007
Census 2011
Annual surveys
STATS SA
•
Community Land Rights
DLA
DPLG
Nyandeni Municipality
69,220 Geo-referenced points
Nyandeni Municipality
Nyandeni Municipality - attributes
City / Town / Traditional Authority: Koniyaoyo
Village name / Sub place: Tshatshi
Unique ID: 23400160_00063
Geo-referenced Coordinates
Head of Household: Mavela, Nogenile
Feature use: Du (Dwelling Unit)
Dwelling type: Traditional dwelling/hut/structure made of traditional material
Mutale Municipality
22, 810 Geo-referenced points
Mutale Municipality
98 map sheets (1:10 000 scale)
Mutale Municipality - attributes
City / Town / Traditional Authority: Mutale
Village name / Sub place: Masisi
Unique ID: 90600196_00041
Geo-referenced Coordinates
Feature use: Bus (Business)
Business / Complex / Farm Name:
Sedzazwau Restaurant & Café
Dwelling type: Dwelling or Brick structure on a stand or yard or on a farm
Statistics from the Dwelling Frame
MNQUMA (EC122)
FEATURE USE
Urban Formal
Urban Informal
Rural Formal
0
4
0
0
4
Bottle Store
10
6
0
0
16
Business
62
209
10
1
282
386
40
15
1
442
22
6
0
0
28
3,008
59
59
23
3,149
51,548
6,520
3,400
293
61,761
Factory
0
37
1
0
38
Filling Station
3
7
0
0
10
Garage
1
3
0
0
4
Guest House / Lodge
1
6
0
0
7
Market
1
0
0
0
1
1,993
347
87
22
2,449
18
37
6
2
63
152
29
7
15
203
Sports, Oval, Stadium
1
4
0
0
5
Park
0
1
0
0
1
Police Station
2
5
0
0
7
Post Office
9
5
0
0
14
Bank
Church / Place of Worship
Day Clinic
Demolished Structure
Dwelling Unit
New Dwelling Under Construction
Offices
Other
Traditional
TOTAL
Holiday Home
58
47
0
0
105
1
9
0
0
10
472
52
5
5
534
Convent/ Monastery/ Religious Retreat
1
0
0
0
1
Old Age Homes
0
1
0
0
1
Hospital/ Frail Care Centre
1
2
0
0
3
63
0
0
0
63
Prison/ Correctional Institution/ Police Cells
0
2
0
0
2
Boarding School Hostel
1
0
0
0
1
Student's Residence
1
40
0
9
50
28
28
9
0
65
406
29
6
0
441
26
1
1
0
28
6,432
208
509
64
7,213
0
192
0
0
192
64,707
7,936
4,115
435
77,193
Residential Hotel
School
Initiation School
Workers Hostel
Shop
Storage Room
Vacant Dwelling
Vacant Stand
TOTAL
Statistics from the Dwelling Frame (cont.)
Figures represent only number of spatial points per feature class
Dwelling Frame maintenance

Joint partnerships with local municipalities, SA Post Office and other Government
& private agencies (joint maintenance for one common frame)

Update photo coverages – change detection

Digital gps referenced video – cameras on vehicles or helicopters
Local Municipalities capacity for
maintenance of the Dwelling Frame
Overall Spatial Data Capacity: 2005
Aerial & Satellite Photography
•
Aerial
&
Satellite
Photos
•
•
Entire country covered with Spot 2.5 satellite photography,
replaces old topo-sheets (Joint project with SAC, Department of
Agriculture, Stats SA)
Detail aerial photographs (Jointly with DLA)
Endeavour to partner with other Government Departments,
Local municipalities, Metros, other bodies like the SAEOS, for
annual complete coverage of aerial & satellite photography
for SA
Aerial
&
Satellite
Photos,
Census 2001
Aerial
&
Satellite
Photos,
March 2007
Aerial
&
Satellite
Photos,
March 2008
•
Aerial
&
Satellite
Photos
•
•
Build & maintain land cover & land use coverages as a national
asset
Research into building more reliance on aerial & satellite data
(more Office-work than Field-work)
Research into deriving statistics like dwelling counts, dwelling
types, estimated population, population changes & movements,
…, for intercensual updates
GPS & GPRS, Surveys
as a testing ground
•
•
•
•
•
Re-vamp map layouts, bulk map production applets, map reading training
Use of GPS (sub-meter accurate) & GPRS technology (direct digital capture)
GPRS – data sent to head-office every hour
Immediate identification of problems and remedial actions
Our plans are that the dwelling frame becomes the frame for householdbased surveys & censuses. Debate: Dwellings - Households
EA Demarcation,
preparing for Census 2011
EA Demarcation Methodology

Dwelling Frame basis for EA demarcation. Provides digital listings of dwellings.
households?

Update photo coverages

Community Survey

Place name areas

Standard Geographic Frame

More intelligence into the calculation of EA size (indicators like length of questionnaire, literacy levels,
available daylight hours, distance, area, terrain, etc. Exploring time series analysis from data from 1991,
1996, 2001 censuses, using geo-statistics clustering of dwelling points to determine average EA sizes for
the main settlement types.

Geography types & EA types

Line database

Urban & rural
Dwellings or
Learning’s from the PRESENT & going into the FUTURE
• Registers pillars of statistics. (Business, Population,
Address - Registers)
• Building more reliance on spatial data, enforcing the
Spatial Data Infrastructure Act (SDI Act)
• ‘Geography’ (or spatial technologies & data) an equal
partner in the production & dissemination of ‘statistics’
Thank You
Maximising on Aerial & Satellite Photos, common issues
OFFICE POINTS
FIELD POINTS
OFFICE POINTS
FIELD POINTS
FIELD POINTS
OFFICE POINTS
Maximising on Aerial & Satellite Photos, common issues
EA Settlement
Type
Office-based points
Fieldwork-based
points
Urban Formal
36 580
37 850
1 270
3.47
Urban Informal
4 049
4 752
703
17.36
Rural Formal
17 744
20 325
2 581
14.55
Traditional Area
250 234
270 736
20 502
8.19
Total
308 607
333 663
25 056
8.12
Difference (Abs)
% Difference
Maximising on Aerial & Satellite Photos, common issues
Attribute
Settlement Type
Urban Formal
Urban Informal
Rural Formal
Traditional Area
Municipality
100%
100%
100%
100%
Traditional Authority
N/A
N/A
N/A
75%
Administrative Area
N/A
N/A
N/A
0%
City/Town/Township
75%
57%
N/A
N/A
Suburb
38%
71%
N/A
N/A
Village
N/A
N/A
N/A
94%
Alternative Village Name
N/A
N/A
N/A
0%
Sub-Village
N/A
N/A
N/A
0%
EA Number
100%
100%
100%
100%
Unique ID
100%
100%
100%
100%
Latitude (S)
100%
100%
100%
100%
Longitude (E)
100%
100%
100%
100%
Height
100%
100%
100%
100%
Street Number
0%
0%
N/A
0%
Street Name
0%
0%
N/A
0%
Street Name Suffix
0%
0%
N/A
0%
Maximising on Aerial & Satellite Photos, common issues
Attribute
Settlement Type
Urban Formal
Urban Informal
Rural Formal
Traditional Area
of
0%
0%
0%
0%
Name of Head of Household
(1)
0%
0%
0%
0%
Name of Head of Household
(2)
0%
0%
0%
0%
Visible Number
0%
0%
0%
0%
Source of Number
0%
0%
0%
0%
Feature use
97%
95%
55%
90%
Building/Complex Name
0%
0%
0%
0%
Contact details
0%
0%
0%
0%
Registered Farm Name
N/A
N/A
100%
N/A
Registered Farm Number
N/A
N/A
100%
N/A
Farm Name at gate
N/A
N/A
0%
N/A
Magisterial District
100%
100%
100%
100%
Unit Count
99%
98%
68%
96%
Structure Count
85%
75%
79%
36%
Structure Description
0%
0%
0%
0%
SD Identifier (room)
0%
0%
0%
0%
SD Identifier (bed)
0%
0%
0%
0%
Coordinates logged at
100%
100%
100%
100%
Name obtained from
0%
0%
0%
0%
Surname
of
Household
Head
Photography Coverages for Census 2001
Standard Geographic Frame
Overall Spatial Data Capacity: 2006
Demarcation Census 2001:Satellite images for change detection
Demarcation Census 2001: Videography
Mutale Municipality
- Place name demarcation