Tag: choropleth

This week, in a step towards supporting the above scenario, I investigated how we might generate choropleths to help us visualise the variations in the amounts of household-generated waste across geographic areas in Scotland.

The cube-to-chart executable notebook steps through the nitty-gritty of this experiment. The steps include:

1. 1. Running a SPARQL query against statistics.gov.scot’s very useful data cubes to find the waste tonnage generated per council citizen per year.
   2. For each council area, derive the 3 values:
      • recent – 2018’s tonnage of waste generated per council citizen.
      • average – 2011-2018’s average (mean) tonnage of waste generated per council citizen.
      • trend – 2011-2018’s trend in tonnage of waste generated per council citizen. Each trend value is calculated as the gradient of a linear approximation to the tonnage over the years. (A statistician might well suggest a more appropriate method for computing this trend value.)

      The derived data can be seen in this file.

   3. Use Vega to generate 3 choropleths which help visualise the statistical values from the above step, against the council-oriented geography of Scotland. (The geography data comes from Martin Chorely’s good curation work.)