copyright 2010, the world bank group. all rights reserved. coverage, frames & gis, part 2...
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Copyright 2010, The World Bank Group. All Rights Reserved.
COVERAGE,FRAMES & GIS, Part 2
Quality assurance for census
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Copyright 2010, The World Bank Group. All Rights Reserved.
ROLE OF GEOGRAPHY IN CENSUS
Geography is an integral part of the census frame distribution network coding structure control system dissemination
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Copyright 2010, The World Bank Group. All Rights Reserved.
TRADITIONAL MAPPING OPERATION
Traditional mapping method• Map characteristics are manually drawn on
transparent layers from base maps
• A map is printed when all the required characteristics are on the various overlaid layers
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Copyright 2010, The World Bank Group. All Rights Reserved.
MANUAL versus AUTOMATED
Manual Mapping Operations:• Is very labour-intensive • Is time-consuming• Error prone• Storage and retrieval cumbersome
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Copyright 2010, The World Bank Group. All Rights Reserved.
MANUAL versus AUTOMATED
• Automated Mapping Operations (GIS):– Require high-end computers and storage– Require specialized software– Require intensive training– Are faster– More accurate– Have derivative uses
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Copyright 2010, The World Bank Group. All Rights Reserved.
COST ANALYSIS
1. Planning, design and management– Overall planning of the GIS project– Outside expertise recommended
2. Site Assessment– Adequate space– Adequate services
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COST ANALYSIS cont’d
3. Hardware acquisition– Costs are falling, with power increasing– Hardware capabilities must match software
requirements
4. Software acquisition– Need to evaluate dozens of products– Compatibility: can data be shared?– Evaluate needs: high-end user or visualization?
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COST ANALYSIS cont’d
5. System Configuration/Customization– Distribute work: networked system– Customize GIS software for different types of
users or workers
6. Training– New technology means new skills required– Technology is more and more easy to use,
but changes quickly
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COST ANALYSIS cont’d
7. Database design - Geographic hierarchy– Define attributes and relationships– Identify how tabular census data will be
integrated with map data
8. Data acquisition and Data capture– Look for available data: road network,
hydrographic, elevation, etc.– If not available, plan and do the capture
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ROLE OF GIS MAPPINGPre-Census Activities
• Defining Geographic Hierarchy
Census Operations• Preparation of Base Maps• Delineation of Geographic Boundaries• GIS Database Design• GIS Metadata• Using GIS during Census enumeration
Dissemination and Analysis• Thematic Mapping
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Copyright 2010, The World Bank Group. All Rights Reserved.
GEOGRAPHIC HIERARCHY
Census geography is a nested set, in descending order, of all the standard administrative units that are used to uniquely define an EA
e.g. |a | b |c | d | e ||nn|nnn|nn|nn|nnn|
Where a = province; b = district; c = munic. d = supervisor area; e = EA and n = numeric digit
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SAMPLE GIS ENVIRONMENT
Equipment - Local Area Network (LAN)– ArcInfo: installed only on the server– ArcView: installed on clients (PC)
server
clientclient client
client
printerscanner Tape
backup
digitizer
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COST BENEFIT ANALYSISCosts & Benefits of Census Mapping Options
t im e
h ig h
lo w
ce n su s 1 ce n su s 2 ce n su s 3
co s t
b e n e fit
highcost
benefitlow
time
long-termbenefits
in itia linvestment
Traditional mappingapproach: Costs and benefitsare identical one censusafter another
Digital mapping approach:At initial implementation, costs are high and benefitsare low, but time willreverse the scenario
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COST BENEFIT ANALYSIS cont’d
• Efficiency benefits– Better service
• Tabular data can be immediately linked to geographic data to produce thematic maps
• Tailor-made maps or custom aggregation of census data can be created quickly
– Increased accuracy and consistency• Higher accuracy than sketched maps• Seamless database for whole country• Changes can be tracked easily
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COST BENEFIT ANALYSIS cont’d
• Efficiency benefits– Productivity and cost saving gains, once the
digital database is created, and once staff are trained
• faster editing and updates• more outputs can be generated• more secure archiving system, with less storage
space
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COST BENEFIT ANALYSIS cont’d
• Efficiency Benefits– Income generation
• There is a need for high-quality census data– Government departments of the country and of other
countries– Private companies of the country and of other countries– Educational institutions
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Copyright 2010, The World Bank Group. All Rights Reserved.
USES OF GIS MAPPING
Examples of GIS Mapping Uses:– Support election activities
• Statistical geographic boundaries associated with population census data help to establish voting districts
– Epidemiological analysis• To locate and estimate population at risk to diseases• Helps to plan eradication measures
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USES OF GIS MAPPING
• Demand for statistical data– Plan educational and social services
• Helps forecast demand on various services• Plan the location of new facilities (school,
hospital, etc.)– Utility service planning (water, electricity,
etc.)• Assess current and future use of service• Manage physical infrastructure
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Copyright 2010, The World Bank Group. All Rights Reserved.
USES OF GIS
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Copyright 2010, The World Bank Group. All Rights Reserved.
CONCLUSION
• GIS is potentially a very useful tool• Can be cost effective• Requires preparation• Requires training• Improves timeliness of EA delineation• Improves dissemination in a spatial format• Allows spatial analysis
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