I was, however, less impressed with the graphic they included as a supplement to the story. A few pages in, I discovered this....
The graphic they chose was an area chart where each school district is listed alphabetically along the x-axis and three different dollar values (2012-13 Budget, 2012-13 Local Revenue, 2012-13 State Revenue) are plotted along the y-axis. Each dollar value is encoded with a different pattern to differentiate the values.
Many readers can probably guess where I'm headed with this critique, but let me preface the following with a bit of background. The Times just recently started using Tableau Public to add a data visualization layer to their stories. I noticed this development a few months ago and applauded them on Twitter at the time for taking that step. A short time later I took a jab at them for a pie chart viz they included in the paper edition (which did look slightly better in color online, but hey it's still a pie chart). Since then they've done a few more stories which have included some Tableau graphics. So cheers to the Times for making an effort to use data visualization as a supplement to their journalism, but jeers to the Times for not making an effort to doing their data viz the right way. Anyway, continuing...
My beef with the Times' chart choice is that area charts should be used to show time-series relationships. Connecting the school districts using a line suggests that there is some kind of trend over time. In this case, there isn't. The area chart, quite simply, is a poor choice.
Using a powerful tool like Tableau unchecked - without some understanding of data visualization best practices - results in output like we see here. Tableau does nudge users in the right direction of choosing the correct chart type in the 'Show Me' dialog when it indicates that area charts should include a 'Date' dimension. But that wasn't enough here. Instead we see a graphic that was likely the result of something along these lines: "I have this great data set and I want to use it to supplement my story. I haven't used an area chart before and it looks pretty cool, so I'll choose that one and go with it."
Now I very rarely use area charts in my own work, but I do know how and when they should be used. And this is absolutely not a use case for an area chart. So I took a few minutes to grab the same data that the Times used and did a simple makeover as, you guessed it, a bar chart. With a couple slight modifications to help add some of the context of the original story.
Here's a link to my interactive redesign...
With the bar chart on the left, I'm showing the ranking of schools from those with the greatest surplus (under budget) to those that with the greatest deficit (over budget). The "bar in bar" chart on the right adds some context showing each district's 2012-13 Budget and 2012-13 Total Revenue.
I don't routinely deal with financial data, but it feels like we're making certain assumptions about this data that could be misleading. The data that the Times used seems to indicate that school district revenue comes solely from state and local taxes - maybe that's true, maybe it's not. But that's what was included in their chart so that's what I included in my makeover.
I'm sure there are many other ways this data could be represented - a scatter plot immediately comes to mind. But for this use case, choosing between an area chart and a bar chart - the bar chart wins every time.
The intent of this particular exercise is not to indicate that a bar chart is the only way to represent this data. Instead, it's to indicate that an area chart is not the way to represent this data. And, maybe more importantly, do some homework before choosing your next chart type.
The source data I used came from this workbook
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