In lab 2, the goal was to learn how to download data from the United States Census Bureau and map this data in ArcMap while learning new techniques and gaining new knowledge along the way. For this assignment specifically, I was to take demographic info (population and a topic of my choice - housing units) of Wisconsin counties, download the data and state map, and use these to create a map of each.
I learned that the US Census Bureau, which contains quality demographic data, has a plethora of downloadable data available to the public that can be used, in this case, to create a map in ArcMap. The general methodology of creating a map with this data is to obtain and format the data, join the attribute tables, and then finally map the data. For each map, I first went to the Census Bureau website and selected a topic in the advanced search window (population and housing units). Next, I went to the 'Geography' section and selected 'All Counties' in Wisconsin which narrowed down the selected data to the state of Wisconsin and its counties. After this, I downloaded both sets of data, which were in the form of zip files, and unzipped each to access the data. I opened both CSV files of the downloaded census data and saved the one that contained the tabular data as an Excel Workbook file to be used in ArcMap. Using ArcMap, I connected to the folder that the downloaded data were saved in and dropped in the Wisconsin shape file and the previously saved tabular data. The next step was to open the tables of each layer and find a common field between the two in order to join them. Each had a GEO#id field, and by going into the 'Join and Relates' tab of the Wisconsin shape file, I was able to use the common field to join both tables. After this, it was almost time to map the data, but first the population data needed to be tweaked in order to map it. From the table menu, I went to "Add Field", selected "Double" for the field type, and used the "Field Calculator" option to make the population data available for mapping. At last, the data was ready for mapping using a graduated colors map.
The results of each map have quite similar patterns. Both feature Milwaukee County as having the largest values for each data mapped -- total population (See inserted map, left side) and housing units as a percent of the state total (See inserted map, right side); Dane and Waukesha counties contain the next highest totals, being grouped in a class together on each map. For the most part, the remaining counties on each map match up with each other as far as how they are classified suggesting that population and housing units are directly related. What does differ is that more housing units appear in northern Wisconsin in comparison to the population that is found in the region.
Link to my housing units Web-Map: http://uwec.maps.arcgis.com/home/item.html?id=8e25420efe1e43da97bb4419f5762f1b
Source: U.S. Census Bureau. American FactFinder. Retreived October 28, 2015, from http://factfinder.census.gov/faces/nav/jsf/pages/searchresults.xhtml?refresh=t
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