Welcome to the acs-alchemist wiki!
The ACS Alchemist is a desktop tool for extracting data from the American Community Survey down to the blockgroup level. A powerful GUI and a command line interface are both provided, so you can fine tune your export in one, and automate your export in the other.
About ACS Alchemist
This project was supported by Award No. 2010-DE-BX-K004, awarded by the National Institute of Justice, Office of Justice Programs, U.S. Department of Justice. The opinions, findings, and conclusions or recommendations expressed in this software are those of the author(s) and do not necessarily reflect those of the Department of Justice or Temple University.
The software was developed by Azavea in connection with the National Institute of Justice grant awarded to Jerry Ratcliffe and Ralph Taylor of Temple University's Center for Security and Crime Science.
For a brief tutorial about installing and using the utility, watch this YouTube video.
Frequently Asked Questions
Where can I download it / Where can I find the installer?
What is a variables file? Where can I find the variables?
In order to export data from the American Community Survey, ACS Alchemist requires you provide a list of IDs for the estimates you'd like to retrieve. You can find these IDs in the "Table shells" files for the particular year you're looking for. We've provided the 2009 and 2010 5-year estimate table shells files, and you can download them here:
What is the variable file format?
The format for the variables file is simply a list of IDs, and you can provide an optional label if you like. The labels must conform to shapefile column guidelines, and cannot exceed 10 characters.
Example Variables file:
B00001001,ALLPOP B01001002,TOTALMALE B01001026,TOTALFEMALE
What issues should I be aware of when using data from the ACS?
The census provides tons of great information on this subject, and
- They have provided several free PDF 'books' here: http://www.census.gov/acs/www/guidance_for_data_users/handbooks/
- and there is another good list of pointers here: http://www.census.gov/acs/www/guidance_for_data_users/guidance_main/
Why am I only seeing 2009/2010 5-year estimates, why don't you have "***** ** year" available?
The ACS Alchemist can be expanded to retrieve any ACS data provided with the same folder and file syntax as the 2009 and 2010 5-year estimates. You can copy one of the year config files (such as AcsAlchemist.json.2009.config), and edit the year and folder names to add support as new estimates are added. If there is a large demand to add default support for more years, we will considering adding those as well.
For example, if we wanted to add "acs2009_3yr" we could:
- Copy AcsAlchemist.json.2009.config to "AcsAlchemist.json.2009_3yr.config"
- Change the following values:
"CurrentAcsDirectory": "acs2009_3yr", "CurrentAcsAllStateTablesDirectory": "2007-2009_ACSSF_By_State_All_Tables" "ColumnMappingsFileName": "2007-2009_SummaryFileXLS"