2 Replies Latest reply on Apr 20, 2016 8:27 AM by Thomas Exter

    Trouble with ACS Mapping

    David Swift

      I'm working with American Community Survey (ACS) data I've run into a problem. I'd like to be able to map the PUMAs but don't have the mapping. I have seen this thread (Can Tableau create filled maps at PUMA level of ACS data? ) but I don't have access to the software to use the TIGER links on the census.gov site. Instead I mapped zip codes to PUMA and CBSAs in a separate worksheet and then linked to my ACS data. I can then use the zip code mapping to create my maps. This presents two problems. First, I still see the zip codes. Is there a way to remove the zip code layer and still keep the mapping? Or more so group the zip codes by PUMA so they are selected together? Second, sometimes I can use the Median calc and sometimes I can't. For example, I have the median age on the map below but if I filter by year I lose the median year. Is there a way to set it up so I can filter as need?

       

      Thanks for any help or advice on how to best map PUMAs/CBSAs and to work with the data across two data sets.

        • 1. Re: Trouble with ACS Mapping
          Thomas Exter

          Hi David,

           

          A couple of questions for you. Do you have a compelling reason to be using the ACS microdata (PUMs files) like the need for custom crosstabs? Or, are you needing exact medians based on the microdata sample as opposed to the published estimates of medians in the ACS summary data? I have posted several census tract level ACS datasets pre-loaded into Tableau based on the 2010-2014 ACS summary data estimates, that is, five years of ACS sample data summarized to standard geographic layers. I prefer census tracts because the ACS provides reasonable estimates at that level and Tableau can automatically roll that up to county and state, for example.

           

          My free ACS data is posted at here at my website www.thedemographics.com under “Demographics for Tableau.”

           

          The census tract data uses a Mapbox background map but you can only create symbol maps based on census tract centroid points not a filled map. As to your first question, as yet Tableau can’t join polygons to form a new, higher level geographic layer, although I think that functionality is in the works. So, you can only show Zip Codes color-coded to PUMAs as you have done, not actually spatially joined.

           

          Hope that helps,

          Tom

           

          PS – I’m interested in any comments people may have about the usefulness (or not) of pre-loaded ACS data at census tract level. Thanks!

          • 2. Re: Trouble with ACS Mapping
            Thomas Exter

            David, I forgot to mention that if you need a census tract to PUMA correspondence table, you can find one here at the Missouri State Data Center.

             

            Regards,

             

            Tom