Today we are excited to share that one of our Tableau Analyst's data visualizations was awarded Tableau Visualization of the Day on Monday, April 16. Decisive Data’s very own Chris Herron recently published a data visualization in Tableau that looks at the number of evictions that happen in the United States each year by state.
Herron found the eviction data from the non-profit group of researches, The Eviction Lab, which was founded by Princeton University sociology professor Matthew Desmond. The Eviction Lab was created to make nationwide eviction data publicly available and accessible in the hope that the data is used by policymakers, community organizers, and others interested in understanding more about housing, eviction, and poverty in their own local communities.
Chris's Inspiration for this Data Viz
Desmond published a book called "Evicted" back in March of 2016, that goes over this data and the housing crisis in the United States as a whole. Herron read this book recently, and grew interested in creating a visualization with the free data provided from the Eviction Lab.
“I recently read "Evicted" and I loved it, I was very moved by the story,” Herron said, “Just last week I heard Desmond during an interview on NPR that talked about the Eviction Lab, and how he had just released the data to the public for free.”
Herron would add, “Instantly a light bulb went off in my brain, and I went to Eviction Lab to pull the data to create a visualization that mapped out the United States eviction totals.”
After pulling the data from The Eviction Lab, Herron had to do some data preparation in Alteryx before he could start visualizing the data. According to Herron, he had to get the data set for each state and then merge the data together in Alteryx, before moving on to Tableau.
Designing the Visualization Using Best Practices
It's a best practice to whiteboard or sketch the dashboard before jumping in to build the visualization.
When creating the heat map of the United States eviction totals, it was extremely important to consider what colors were being chosen to be presented in the visualization. Herron said that he wanted to highlight high eviction rate states with a lighter color that draws the reader’s attention, so he created a custom color palette in Tableau to use the specific range of colors chosen in the visualization.
“I chose dark to draw less attention, and the lighter ones that are more severe, because your eyes will move to that immediately,” Herron said.
Tableau Visualization Features
Another feature of the Tableau Visualization is the eviction rate trending graph on the right side of the viz. This graph shows the eviction rate in a trend line that goes back to 2001 for every state that is featured in the map. The specific graph is an area chart that has a dual axis with circles as the data points.
The most unique feature / the most advanced feature used in the visualization was a technique called “lightbox technique,” according to Herron. If you select the four arrows directly above the state Maine, it will show all years of this data set at once.
Currently, when looking at the dashboard, you can select a year and filter to that year, but if people want to see the progression over time, just click on the four arrows above Maine. The resulting visual design is called small multiples of the US by year.
Telling The Data Story of US Eviction Rates
The visualization shows that eviction rates in the Southeast United States is still fairly high and has not really gone down in recent years. Also, areas like Arizona and Michigan have the highest eviction rates, while places in the Midwest like Nebraska or Wyoming do not have that many evictions.
This project is a prime example of how data visualization technology, like Tableau, and data transformation technology, like Alteryx, can be key drivers in the global movement for social good. Feel free to play with the Viz below, or check it out on Chris's Tableau Public Profile.
Posted by Gage Peake