Vizzuality/cartodb — Issue #441: [thematic] - make numeric choropleth relative to area
Author: tokumine
Created: 2012-01-20 11:50:40+00:00
State: open
Labels: map, new

Currently, the choropleth is basic, but it may encourage users to 'lie with maps' as people will be tempted to map absolute values rather than values 'relative to area'

We should add a checkbox to the choropleth options to let the user calculate a new column 'relative to area'.

This will mean we will have to add column to users table and fill with relative values using something like (my_var / ST_Area(ST_transform(the_geom, 954009)) /10^6) as my_var_per_km2.

In theory we could add the SQL to their query, but I'm not sure how the binning or UI would work in that case.

@jatorre @saleiva @andrewxhill - comments?