[postgis-users] Thematic Maps Demo

[Stephen Woodbridge]

Hi all,

Sorry for the cross posting, but I said I would follow up it a url to 
some example thematic maps I have been working on. All the hits, and 
demographic information is coming out of postgres and the zipcode 
polygons are in postGIS, and placenames basemap layers are coming out of 
shapefiles.

http://swoodbridge.com/test/postgis-maps.php

This is an attempt at displaying hits by zipcode and comparing that 
against income or population by zipcode. The income and population 
values are scaled into 8 percentiles ranges and used to color the 
zipcode polygons. The hits are scaled into 8 ranges and used to display 
the circles or asterisks and sizes from small to large.

In the first row of maps, I only display the top ranked hits.
On rows 6+ the size of the font displaying the zipcode indicates the 
range of the hits.

This still needs more work to figure out how to best display all this 
information at the various scales. And for that matter what is useful 
from an analysis point of view. I have hundreds of tables of demographic 
information, I would like to know how to correlate the hits against the 
various tables to find out if any of them a particularly significant or not.

Open to any ideas suggestions or pointers.

Thanks,
   -Steve