Background info: I'm a GIS consultant on a transportation planning project in San Bernardino County, and my client wants to see a series of choropleth maps that show demographic data for our project area. One variable the client wants to see is population change in the project area between 2000 and 2010, using Census 2000 and Census 2010 data.While it is very easy to create two maps of the study area in ArcMap with data from the Census Bureau- one map showing the population in the area by census block group in 2000, one showing the 2010 population by census block group- it is not easy to draw accurate or fast conclusions about changes in population between the two time periods because the Census geographies (i.e., census blocks, block groups, tracts) change with each Census as the population changes. In the case of the study area, in 2010 there are roughly double the number of census blocks than were present in 2000 because the population has grown. This difference in the size, number, shape, and ID numbers of the census block groups makes it impossible for me to do an apple-to-apple comparison of the data- there are no common points of comparison to, say, do a tabular join in ArcMap.
So, I turned to Community Analyst, which I just learned about, because it seemed like it could be the answer to my problems. And in some ways, it is, because CA does allow me to compare census data between different years, based on one year's geography. Using CA, I can compare 2000 and 2010 total population figures for my study area, using 2010 census boundaries only, so that I can just toggle between 2000 data and 2010 data, without changing the geographical boundaries of census block groups. This is great! However, while CA looks great onscreen, it doesn't translate well to PDF or a screen cap. The PDF function cuts off the outer portions of my study area, and the screen cap is low-res- it's really hard to read labels and names on the map.
What would be ideal is to have a Community Analyst extension, or some other mode access, for Desktop that allows users to have access to the demographic info, etc. in CA, but the customizability and graphics capabilities of ArcMap. It would also be great to be able to export data, including feature classes, from CA to Desktop, in order for the user to make print-quality maps, using the great data options that are built in to CA. As it stands, there isn't a way for me to export data from CA in a format that I can plug into ArcMap. While I can download a data table of census info from CA, I cannot join the data to a feature class/shapefile of census geography (such as, in my case, 2010 census block groups) that I downloaded separately from the Census/TIGER site. When I tried to do this, I found that the unique identifier numbers associated with block groups were in totally different formats between the TIGER file and the CA table. I hit a dead-end.
I think Community Analyst is a good tool, with the potential to be a great tool. Improved graphics, increased customizability, and the ability to cross platforms from server- to desktop-based would be fantastic. I think there are a number of Desktop users, like those who use Business Analyst, who would readily use CA in this way.
Thanks for the platform to share my idea!
