Digital Census Mapping Process: United Nations Statistics Division Expert Group Meeting on Contemporary Practices in Census Mapping and Use of GIS 29 May -1 June 2007 New York Digital Census Mapping Process: a conceptual framework and different implementation approaches United Nations Statistics Division

Summary Introduction-Mapping “Revolution” Census Mapping Process: Conceptual Framework Different Implementation Approaches GIS, GPS, Digital Imagery: More integrated Institutional/Organizational Issues Critical Success Factors Concluding remarks

Introduction Mapping “Revolution”: NSOs and Geospatial Technologies: Shift: Manual to Digital Paper map vs GIS map Static vs interactive User needs: increasing demand NSOs and Geospatial Technologies: Full advantage vs slow adoption Real issue: integration for improvement

Census Cycle Pre-Census Census Post-Census (Pre-enumeration: Maps provide cartographic basis for the delineation of EAs) Census (Enumeration: Maps support data collection, monitoring) Post-Census (Post-enumeration: Maps make it easier to analyze, display and disseminate)

Geographic Information Process (illustration) Acquisition Aerial Photography Surveying. Maps Remote Sensing GPS Census & Surveys Management/ Analysis GeographicDataBase GIS Internet Display/Dissemination

Census Mapping Process: conceptual framework Census Mapping Operations: A Geographic Information Process Different Mapping Needs at the three stages: Pre-enumeration Large-scale maps for delineation of EAs Enumeration Large-scale maps for enumeration Mid-scale for monitoring Post-enumeration Mid and Small-scale maps for dissemination

Pre-enumeration stage Pre-enumeration (EA Map Production) Large-scale maps EA units Geocoding System Census Database Digital Mapping GIS Satellite Imagery Aerial Photo. GPS

Census Enumeration Stage Pre-enumeration (EA Map Production) Large-scale maps EA units Geocoding System Census Database Digital Mapping GIS Satellite Imagery Aerial Photo. GPS Large-scale maps Large & mid-scale for sup. Mid- & small-scale for manag. Admin./Statistical Units GPS GIS Digital Mapping Enumeration (Census Data Collection)

Post-enumeration Stage Mid- & small-scale maps EA update Statistical Database Databases (Maintenance) GIS Internet Mapping (Map Server) Digital Mapping Pre-enumeration (EA Map Production) Large-scale maps EA units Geocoding System Census Database Digital Mapping GIS Satellite Imagery Aerial Photo. GPS Large-scale maps Large & mid-scale for sup. Mid- & small-scale for manag. Admin./Statistical Units GPS GIS Digital Mapping Post-enumeration (Census Data Dissemination) Enumeration (Census Data Collection)

Geospatial Technologies at all stages Pre-census Census Post-Census (Enumeration) (Post-enumeration) (Pre-enumeration) Digital Mapping Digital Mapping Statistical Database Census Database Databases Maintenance GIS GIS Aerial Photo. GIS Satellite Imagery GPS Internet Mapping GPS Administrative and Reporting Units EAs Units

Different Implementation Approaches Various combination of geospatial tools: depend on the approach chosen by NSO (needs vs resources) Three main approaches: Post-census Full Census Program Mixed Approach

Post-Census Approach Pre-census Census Post-Census (Enumeration) (Post-enumeration) (Pre-enumeration) Digital Mapping Databases Maintenance GIS Internet Mapping Administrative and Reporting Units

Post-Census Approach No extensive work under pressure Need can be limited for maps with administrative and reporting units Learning Process Early planning exercise

Full Digital Census Mapping Program Pre-census Census Post-Census (Enumeration) (Post-enumeration) (Pre-enumeration) Digital Mapping Statistical Database Digital Mapping Census Database Databases Maintenance GIS GIS Aerial Photo. GIS Satellite Imagery GPS Internet Mapping GPS Administrative and Reporting Units EAs Units

Full Digital Census Mapping Program Development of an EA Database Rudimentary digital maps Geo-referenced EA maps Reference layers: roads, rivers, Landmarks, etc. Digital Postal Address registry Digital Database of dwelling units Statistical Database GIS and Internet-based Dissemination

Mixed Approach Pre-census Census Post-Census (Enumeration) (Post-enumeration) (Pre-enumeration) Digital Mapping Digital Mapping Statistical Database Census Database Databases Maintenance GIS GIS Aerial Photo. GIS Satellite Imagery GPS Internet Mapping GPS Administrative and Reporting Units EAs Units

Mixed Approach Combination of existing maps + satellite imagery + aerial photos: up-to-date maps for major cities (or regions) for EAs + traditional techniques for other cities and rural areas Geographic Database: Evolving Prototype

Recent Technological Developments GPS: Greater accuracy, reduced cost, waypoints displayed real-time in a GIS software; Satellite Imagery: Higher resolution, positional accuracy, and GIS-readiness; Digital Arial Photo: extending its scope to small urban areas Mobile GIS: Capture, manipulate, analyze and visualize data in the field in real time; GIS+GPS+ Image Processing: Better integration.

Institutional/Organizational Issues A specialized in-house Cartography/GIS unit Building technical and human capacities National Spatial Data Infrastructure (NSDI) Basic data Population Datasets and Geocoding System: basic components

Critical Factors Ensuring Commitment for a long-term digital census mapping program; Conducting a comprehensive needs assessment; Tailor-made methodology of integration; A Permanent unit for Cartography/GIS within the NSO; Partnership and cooperation; Capacity Building for sustaining the census mapping program.

Concluding Remarks For 2010 the P&R recommended the use of Geospatial technologies for improving traditional methods of census mapping Digital Census Mapping Process: spanning all the stages of census data collection, analysis and dissemination Implementation Approach: each country has to find its own best possible solution Best Practices - Revision and Update of the Handbook on GIS and Digital Mapping

Thought of the day: GIS, GPS and Remote Sensing bring sense to censuses!