The goal of lab two for GIS 1, was to learn how to download and map data from the U.S. Census Bureau. The U.S. Census Bureau has a mission to serve at the leading source of quality data about the nation’s people and economy. I had to follow several objectives to obtain this goal, including downloading datasets from the U.S. Census Bureau, joining data tables, and creating a web map.
Methods
To begin, we had to obtain census data by choosing a variable of interest from the U.S. Census Bureau (http://factfinder.census.gov/faces/nav/jsf/pages/searchresults.xhtml?refresh=t). I choose people and basic count/estimate as a topic, and all counties in Wisconsin as the geography. From there, I downloaded an SF1 data set, because it is the basic standard census data. The variable I downloaded was total population from the 2010 SF1 dataset. After the dataset was downloaded as a zip file, I needed to unzip the files and save the CSV files containing tabular data as an excel workbook file. Then, I downloaded the map of Wisconsin counties as a shapefile.zip and unzip those files as I previously did. After obtaining the appropriate data, I had to join the data together to create a map in ArcMap.
First, I added the shapefile containing the counties of Wisconsin, then because this file contains no census data, I added the excel file I created earlier containing the tabular data of population. In order to map the population, I had to join the excel file and the shapefile tables together using the same attribute field (GEO#ID). By joining the same attribute field I was then able to map the total population of Wisconsin by county. I wanted to create a graduated colors map with my population values, but because the values were imported as a string field type, the values could not be mapped quantitatively. To fix this, I added a new field in the attributes table that was a double field type, containing the original values from the population data field. Then, I was able to map using graduated colors.
Second, I needed to create a new map in the same file, but under a different data frame. This time my variable of choice was males aged 25-29 in all counties of Wisconsin. I went to the U.S. Census Bureau website and downloaded a 2010 SF1 100% data dataset. I followed the same workflow as before to download the data, unzip and create excel files, and map the data for my variable of choice. Additionally, I had to join the shapefile of the Wisconsin counties and the excel file containing the tabular data on male population ages 25-29. Again, I had the same problem trying to create a graduated colors map because the values were imported as a string field type, not a double field type. So I created a new, double type field in the table containing the values for male population ages 25-29. Then, I was able to map using graduated colors, but I had to normalize my data by the total population of each county. I mapped the population of males aged 25-29 and normalized it by the total population.
Following these steps, I created a cartographically pleasing layout containing both maps of Wisconsin. While doing this, I had to consider changing the projection of the data frame to better suit the state of Wisconsin, and add the appropriate map elements including an author, source, title, legend, scale, and north arrow. The projection I used was NAD 1983 (2011) Wisconsin TM (US Feet). To finish my project, I added a light grey, canvas basemap.
After creating those maps, I had to publish a web map on ArcGIS Online, using my second variable. I made a copy of my second map, deleting all other items including all other data frames, basemaps, original joined shapefiles, and tables. I exported all of the features of my second variable into a new shapefile and imported my symbology properties from my previous map. In ArcMap, I signed into my University of Wisconsin – Eau Claire account on ArcGIS Online, where I then created a feature service from this new ArcMap document. I had to include a service name, “Wisconsin_Demographic_Information_Pingel,” an item description, and tags before I was able finish creating my feature service. After the feature service was created, I was then able to analyze and publish my web map. Using ArcGIS Online (http://www.arcgis.com/home/), I logged onto the UWEC Geography and Anthropology ArcGIS account to share my map. Before sharing my map, I needed to update some of the contents such as the map name and display attributes.
Results
Patterns on the map indicate that the highest male population between the ages of 25-29, are in central and southern Wisconsin. Additionally, the most of the counties with the highest male population (Eau Claire, Brown, Dane, La Crosse) are counties within the University of Wisconsin college community system.
(http://uwec.maps.arcgis.com/home/webmap/viewer.html?webmap=f46e642bf6e04872abdb34b82982e842)
Sources
U.S. Census Bureau and ArcGIS Online:
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