Mapping Kansas City: KCResearch Tries out Cartography (with some help)
Mapping It Out
The recent Infinite KC mapping contest recently got our gears turning at KCResearch. We have a lot of different maps in the database that cover everything from demographic maps to environmental studies. Adding to our love of maps we recently attended a workshop for using different data visualization and mapping tools. Eager to use them we decided to use Rhonda Roosa’s contest submission and make a map of our own using Batch Geo, a free, online application that uses Google Maps in conjunction with your own data to generate an interactive map.
Though her entry did not win the library’s contest, Rhonda’s idea to show locations of green spaces and surrounding household income is the perfect kind of map for our data-loving brains at KCResearch. It combines census data and city data to provide detailed, colorful, and interactive information. We took this opportunity to make two maps showing Green Space Locations and Average Household Income and another for Green Space locations and Median Household Income.
Using data from a 2009 Parks Reference Book released by the City Parks, Recreation, and Boulevards Department and the 2010 Census we made the map by taking a list of parks and locations in Kansas City, MO (doing the entire metro area might have taken months to plug in all the data), finding out the census tract for each of the 218 parks and tracking down the most recent average and median household incomes for each census tract that holds a park or parks.
Explaining It All
Census Tracts are small statistical divisions of a county and are small enough areas to get detailed information about the demographics surrounding each green space. On average a census tract has about 4,000 inhabitants, but in urban settings like Kansas City, the tracts hold about 1,500 people on average. The two maps presented here show Average (or mean) household income, which is the sum of all household incomes divided by the number of households and Median household income, which is the middle household income of all the households within the census tract.
There are some instances where an average number adequately represents the demographic area, but other instances—when there are outliers (either very low or very high figures) the more accurate representation is the median number.
Mastering the Map
Both maps plot out the location of each public green space (park, greenway, garden) with a color-coded inverted teardrop indicating the income range. If you click on the inverted teardrop it will reveal name of the park, the census tract, and both the average and median incomes of the surrounding area.
These maps work just like google maps—click and drag to move around, zoom in and out by hitting the + and - on the side or scrolling with your mouse’s clickwheel. To see the different income levels and park distribution in more detail, at the bottom of the map you can click the color of the income level you wish to see. To return to all, simply click on the color you are viewing again.
To change the map type (it gives you 3 options: map, terrain, satellite) you can change it in the drop box at the upper right hand corner. You can also use the search box to search for a particular park or census tract.
One of the goals of KCResearch is to present data and encourage interaction, and maps are an excellent way to do this, particularly because they present a visualization of information. The Parks and Income Maps we made are one example of ways to combine information found within KCResearch with another free online tool. So thanks for the great idea, Rhonda Roosa!