This map displays New Zealand population data from the 2013 census. Green dots represent the Māori population, blue dots represent the European population, and red dots represent the Asian population.

How It Was Made

The population data for Māori, Europeans and Asians residing in New Zealand during the 2013 census was taken into QGIS software, and the corresponding number of dots (one dot to one person) were overlaid on the correlating mesh-block. The dot map layers were then exported as shapefiles, and raster tiles were generated for each zoom level using the Mapnik toolkit. The tiles were then uploaded to the web server, and the Leaflet JavaScript library was used to display this in the browser.

The Data

The population data from the 2013 New Zealand census is publicly available from Statistics New Zealand and was retrieved through the NZ.stat tool.

Data Accuracy and Privacy - Can the dots reveal personal information and locations?

The original datasets are limited by Statistics New Zealand to protect privacy where information might reveal the identity of a person – for example, if they are the only person living within a meshblock then their data is suppressed (removed from the dataset) and marked with a C in the dataset.

The process for creating a dot map inside QGIS software involves randomly scattering a dot for each person within their respective meshblock; the result is that each dot does not truly represent the geolocation of a person.