Dissemination with GIS United Nations Statistics Division 2010

Dissemination with GIS United Nations Statistics Division 2010 World Programme on Population and Housing Censuses: Subregional Workshop on Census Cartography and Management 22 -26 October, 2007, Port-of-Spain, Trinidad and Tobago Workshop on Census Cartography and Management - October 2007

Census dissemination o A census is not complete until the data collected is made available to potential users in a form suited to their needs o The data may be: n included in published tables and reports for general distribution n produced as tables in unpublished form for limited distribution n stored in a database and supplied upon request, or disseminated online (in this case it will be available only to connected populations) Workshop on Census Cartography and Management - October 2007

Census geographical units o The census provides information at any geographical level, pre-defined or user -defined Workshop on Census Cartography and Management - October 2007

The power of maps o Maps visually communicate a concept or an idea o Maps summarize large amounts of information concisely o Maps are often meant to support textual information o Maps can be used for description, exploration, confirmation, tabulation o Maps encourage comparisons: n Between different areas on the same map: where are population densities highest? n Between different maps: is child mortality higher in the districts of province A than in province B? n Same area: where and by how much do literacy rates for males and females differ in the districts? n Between maps for different time periods: did fertility rates decline since the last census? Workshop on Census Cartography and Management - October 2007

GIS provide advanced functionalities for census dissemination o Combination of: n Census database: data at any geographical level n Geographical database: geographical structure of the country + cartographic representation Workshop on Census Cartography and Management - October 2007

Different Uses of Maps o o o Geographical selection Direct selection of a user-defined area Area delineation Buffer zone Areas of influence Modelling: spatial smoothing Workshop on Census Cartography and Management - October 2007

Geographical selection Use this map to navigate to your area of interest by drilling down to the Geographic Areas that you require. Workshop on Census Cartography and Management - October 2007

Direct selection of a user-defined area. . . o The user describes the area on which he needs aggregated data by clicking on the components: for example, municipalities Workshop on Census Cartography and Management - October 2007

Area delineation o E. g. Interactive determination of school districts by looking at the number of children in each school and then aggregating census enumeration areas Workshop on Census Cartography and Management - October 2007

Buffer zone o How many people live within a five mile radius from the hospital ? Workshop on Census Cartography and Management - October 2007

Areas of influence o Commuting distances: daily commuters flow Workshop on Census Cartography and Management - October 2007

Modelling: spatial smoothing o Growth rate of the population between two censuses Workshop on Census Cartography and Management - October 2007

Uses of Graphs: Enriching the Understanding of GIS Data Sets o o o Exploratory Spatial Data Analysis Linked Maps, Graphs & Tables Dynamic Feature Selection Visualization over Time Animation Workshop on Census Cartography and Management - October 2007