This section is one of a series on mapping demographics. Here we start with a hands-on approach to making a map in the Washington, DC area focused on census blocks optionally superimposed on OpenStreetMap layer. Subsequent sections will build on this base. We will get to the objective of enabling you to put your own address-related data on a map combined with data from Census 2010 and American Community Survey. We will make the map view shown below in this session. Details follow.
“A picture is worth a thousand words.” So true. But when it comes to “map pictures,” that is only the beginning. Mapping/GIS tools offer the additional element of geospatial views and analysis. One example is site analysis where, for example, a radius view around a location can be translated immediately into data such as size of market or size/nature of impact area.
As maps and mapping tools have proliferated the Internet, it remains elusive to develop good custom maps that convey patterns of interest. Many organizations defer getting into these applications because they are viewed as complex and required specialized skills and staff. Yet the benefits are enormous. Decision-making can be enhanced in ways unparalleled by using tabular data. As technology advances, tools become more complex; keeping up with change can be challenging. Read ahead, we can enhance capabilities in an easy, no cost, expandable manner.
Census blocks are the smallest geographic area for which Census Bureau data are tabulated. The approximate 11 million Census 2010 census blocks cover the U.S. wall-to-wall. A statistical geographic area defined for the decennial census decade, a census block averages 100 people. In urban areas a census block is often the area covered by a familiar city block. Generally permanent from census to census, census blocks are given a unique identifier comprised of state code(2) + county code(3) + tract code(6) + block code(4). See examples in above view where census blocks are labeled with their GEOID/geocode. More about census blocks.
2. Get Washington, DC GIS Project Files
Expand http://proximityone.com/dmd/2013_dc_dp.zip to folder c:\cvxe\1.
3. Open Washington, DC GIS Project
With CV XE running, and steps 1 and 2 completed, use File>Open dialog.
Open the GIS project file c:\cvxe\1\2013_dc_dp.gis. The view appears as shown below.
Optionally use a second GIS project … open the GIS project file c:\cvxe\1\2013_dc_kalorama.gis. The view appears as shown below.
Next Mapping Demographics section will cover 1) navigating and interpreting map views and 2) how to generalize these steps … any county in the U.S. We will use the above project to show mini-profiles of census blocks:
The mini-profile is auto-copied to clipboard. Paste it into a spreadsheet as shown below.
The above profile shows a mini-profile for census block 11-001-004100-2003. The UR10 status shows that it is urban. Geocodes for other areas and population attributes are shown further down in the spreadsheet (some also shown in previous graphic).
The next post on Mapping Demographic Patterns will be November 19,2013.