A geographic information system (GIS) is a computer-based information system that enables the capture, modelling, manipulation, retrieval, analysis and presentation of geographically referenced data. They are database management systems that allow the concurrent analysis of information from diverse sources, provided they have geographic location coordinates.

Functions

Updating of the Enumeration Area (EA) frame: The Enumeration Area (EA) is a spatial unit specified for household-based surveys and censuses according to the number of dwellings and population size. The GIS unit is the custodian of the national frame used in the sampling process for all household-based surveys undertaken by the Bureau. The National frame is created as a result of each census conducted. However, since censuses are conducted once every ten years (decennial), the frame is updated from time to time through physical mapping exercises. The updating of this EA frame forms part of the routine activities of the unit.

Re-defining the boundaries of the EA: It uses updated household counts and the physical location of social facilities (Markets, Schools, Health facilities etc.), which also serve as reference points to demarcate the EA boundary.

Census cartographic mapping: Maps are needed during all stages of a census or survey. They are required in the planning stages, data collection, analysis and presentation of the results. Census mapping supports enumerators and supervisors to execute their specific assignments, which include the identification of enumeration areas, and the location of households and other structures.

[Sample Enumeration area (EA) Map]