Data Viz Done Right

# Makeover - Chart of the Day: The Seattle Seahawks are one of the NFL best defenses of all-time

Cork Gaines of Chart of the Day has once again provided me with a terrible chart to pick apart.  The idea behind this chart is simple, but the execution is nothing short of terrible.  Let's start with the chart Cork produced:

I like Cork's idea: How did the Seahawks defense rank against the best defenses of all-time?  His primary method of measurement is how each team compared to the NFL average.  Makes sense.

However, there is way too much going on in this chart to make any sense of it.

1. Cork chose to show two measures.  This confused me.  Do all of the teams make up the top 15 in each of these categories?  I doubt it.  It turns out that the measure he's ranking them on is PPG allowed vs. the NFL average.  So why include YPG allowed?
2. Why show 15 teams?  Showing the top 10 makes it easier to find where the Seahawks rank.
3. The point of the article is to highlight the Seahawks, yet he fails to highlight them.  You have to do too much work to find them.
4. The teams are ranked in reverse order.  For some reason, nearly every chart that Chart of the Day produces is sorted backwards.  I suspect they’re using Excel to create their charts.  The best team should be on the left, not the right.  If you don't pick up on that, you might be led to believe that the 2005 Bears had the best defense, when in fact it's the 1975 Rams (who are way over on the right).
5. He's barely highlighting the teams that won the Super Bowl with a tiny asterisk.
6. The chart forces you to turn your head 90 degrees to the right to read the labels.
7. Is the axis needed?  All of the bars are labeled, so I would say no.

I'm sure there are some other things I'm missing, but I'm too irritated with this chart to continue to make myself suffer.

Since I'm in the process of testing Tableau for Mac, I decided to build my version of the chart there.

How did I address my concerns with Cork's chart?

1. I decided to only show PPG allowed vs. the NFL average.  I wanted to keep it simple.
2. I’m only showing the top 10 teams.
3. The point of the article is to highlight the Seahawks, which I've clearly done.
4. The teams are ranked in the correct order, starting with the best defense on the left.
5. I decided to highlight the Super Bowl winning teams by showing the Lombardi Trophy.  This makes it easier to see that having a great defense does not guarantee the title.
6. I've made the team names much easier to read by displaying the text horizontally.
7. The bars are labeled and they all start at zero, so I've eliminated the axis.

It saddens me to see the consistently poor output from Chart of the Day.  They have so much interesting sports data to work with, yet they continue to communicate their stories so, so poorly.  Maybe I should send Cork a copy of Data Visualization: A Successful Design Process by Andy Kirk and/or Show Me the Numbers by Stephen Few.

#### 6 comments :

1. Nice analysis Andy. What you've done makes perfect sense.

Amazing how many basic errors the initial chart makes. The label orientation is the one that winds me up the most.

Cheers
@paulbanoub
www.vizninja.com

2. Such good stuff here, Andy. I love the use of the Lombardi trophy. It might be interesting to swap out the text labels for teams with actual team logos. My assumption is that it wouldn't be too busy since the average football fan would recognize the team logo.

1. Mike, I got the idea for the trophy after seeing your dashboards. I thought about using helmets for the teams, but some teams are listed more than once because they're in different years.

3. Great makeover, Andy! Question: does Tableau give you control over the width of the bars? If so, one (totally nitpicky) suggestion would be to increase the width of the bars a bit - I generally recommend to have the data take up more space than the white space. Question #2: how do I get my hands on Tableau for Mac?? ;-) Nice work!

1. Yes, I can control the width of the bars, but I didn't like how they looked when they were wider than the trophy, though I could make the trophy bigger too.

As for Tableau for Mac, I believe the beta will be starting somewhere near the end of Q1. I'm not 100% sure on that though, just rumors I'm hearing. Get it then.

4. Only tweak I'd consider is to label it "PPG allowed below the NFL Average" and ditch all the minus signs. Nice add to include the "but did you get the ring?" filter with the trophies.