Sunday, 12 February 2017

Makeover Sunday II

This time I'm using a dataset from Jamie Laird, original workbook on Tableau Public . Having worked in remote sensing before, I like the idea of a map as pixels of so many kilometres by so many kilometres, or so many degrees by so many degrees latitude and longitude. This dataset behaves well with Tableau's default Mercator projection(only projection using built in maps) . If you have data closer to the poles you might want to force a geographic projection by using your own map background image.

As always, a couple of calculated fields come handy.
Truncated Latitude and Longitude:
Aggregate the number of responses and force a logarithmic colour scale, with appropriate legend:
case int(log(COUNTD([Response ID])))
when 0 then '<10'
when 1 then '10<x<100'
when 2 then '100<x<1000'
when 3 then '>1000'
Some footnotes on presentation: make sure you have no border or halo on the marks (controlled through colour), and if you really want to treat the marks as individual pixels use the square mark type.

No comments:

Post a Comment