We decided to take Tableau’s Show Me charts and do a squad selection 5-a-side. Andy picked one, then I picked from the remainder. Here’s the “squads” we ended up with, in order we picked them (ie Andy K picked line chart, I picked bar chart, he picked treemap, etc)
I was surprised Andy K took the treemap as second choice. Andy suggested that maps are overrated (shock!). We both agreed that boxplots and bubbles could be happily left on the bench.
What do you think? If you could only use 5 chart types ever again, what would they be?
The trend line is amazing. It shows peaks and troughs and trends. But if you only ever use trendlines to show time, you are missing insights in your data. What’s the best way to show time in visualisation? I cannot answer that: it depends on your data, the story you want to tell, your audience, and many other things.
One of my conference presentations is about visualizing time. This post contains links and resources from the session.
Which way is time?
Time can go up and down as well as left and right. Check out these:
One of the great challenges in data visualisation is balancing functionality and beauty.
On the one hand, you want to make your data viz as understandable as possible. On the other hand, it has to be engaging enough for people to want to use it.
Different dashboards and visualisations need to be at different places on the functionality/beauty spectrum. For example, if you use a dashboard every day for monitoring processes in your business, you need something highly functional which allows you to see outliers as quickly as possible.
I get asked a lot about this balance. My answer is a recommendation to read 3 books.
At the functionality end of the spectrum, you have the books of Stephen Few. I highly recommend Information Dashboard Design. His books give you the foundational knowledge you need. If you are designing dashboards for operational monitoring, you cannot go wrong with this approach.
At this end of the spectrum, I’d put David McCandless. Get Information is Beautiful or Knowledge is Beautiful (I prefer the latter). He makes very popular, very beautiful data visualisations. Almost all are impractical for business situations. If you are trying to communicate anything accurately, I don’t recommend adopting his approach at all. I do not however dismiss what he does.
A sweet spot?
Is there a sweet spot which balances both functionality and beauty? The book which gets closest to acknowledging the tension between function/beauty and helping your deal with it is The Functional Art by Alberto Cairo.
But I can only afford one book…
If you’re starting out in data visualisation, definitely read something by Stephen Few. This is vital to understanding the foundations of data visualisation. Once you’re familiar with those, you can start to add more aesthetic aspects of your visualisations.
Your second book should be Alberto Cairo’s. Finally, get the McCandless book for some inspiration.
Whatever visualisations you build, test them on other people for effectiveness.
Let me know what you think. If you’re going to the Tableau Conference in Las Vegas in a couple of weeks, I’ll be talking about this in my “Visual Design Tricks” sessions.
I inadvertently sparked a debate on Stephanie Evergreen’s blog, “How to show down is good” (go read it – it’s great). In the post, she showed a bar chart whose axis didn’t start at zero (above). The horror!
Not only is this a flagrant breaking of all The Laws Of Dataviz, it came the very week Nathan Yau published an excellent post “Real Chart Rules to Follow”. How dare she!
I commented on Stephanie’s blog that her bar chart was a valid example showing that you could break one of Nathan’s rules, because there’s no such thing as zero weight for an adult human.
Stephen Few made a great point that for Stephanie’s chart, a dot plot would probably be a better option. I agree. Jeffrey made a great point that half the bar length suggests that the person is half as heavy. Fair enough: I agree with that too.
I also agree with my original comment. I’ll defend my comment, but not to the death. Maybe to first scratch but not beyond.
Finally, let me pose a question, to which I am genuinely intrigued to know the answer. Is the chart below valid? All I did was change the title and y-axis of Stephanie’s original chart. Now I am showing zero. Is this ok? 0lbs to target is still 150lbs in real weight.
I’ve blogged before about there being no “correct” way to visualize a dataset. The video below shows how this is the case. Even when data is extremely simple, there are many ways to view it, each being better at answering a different question.
Conclusion? The trick isn’t to think “a line is the best way to show time data.” It’s to consider the question you want to answer. Manipulate and play with the data until the answer is clear.
I was honored to be invited to speak at Visualized:Political Data in Washington DC this week. It was a great event with some amazing speakers. I presented a summary of my UK Election Project (http://impartialityuk.tumblr.com/). Here are the slides – hopefully of some use even though they don’t have the script!
Stephen Few’s excellent book about dashboards: “Information Dashboard Design“. If you are just starting out in visual analytics, this is a must-read book. It’s balanced and sets out good principles which, once learned, can be adapted.
Iraq’s Bloody Toll. This is one of my favourite charts/dashboards of recent years. So simple and yet so effective.
My latest Huffington Post article (published Wed 28 Jan) discusses how amazing our visual system is at seeing very granular levels of detail. Here’s a rather shaky GIF of the different views going from 1 data point to over 10,000:
The inspiration for the column and this post was Ann K Emery’s 2015 data resolutions. I’ve always been a big fan of small multiples, but her specific statement to “do more small multiples” triggered my efforts to break the data out of the charts I’d been making with the Citibike data.
There have been lots of posts celebrating small multiples recently. My favourite is “A Big Article About Wee Things” by Propublica. Go read it! Go on.
What I really need to emphasise is that no single view is the “right” one. Theere’s no such thing as the “right” view. Being able to cycle through these very quickly in Tableau is immensely powerful – each view teases something else out of the data as you feel your way to insight. Each view shows something different and if you can see 30 views in 5 minutes, who knows what insights your data will reveal? What’s certain is that we can reflect on just how complex and yet clear 10,000+ marks appear:
I’ve got this idea for a future theme looking at “3 ages of data viz”. I want your thoughts. Is there something in this idea? Am I right? Are there more? What’s the NEXT age going to bring? What does this teach us about dataviz?
Age 1: The Excel disaster (pre 2000)
The early spreadsheet designers got excited about graphics and gave us 3-d exploded pie charts. If only they’d read some theory about effective dataviz maybe we’d not have had 35+ years of fighting back against dataviz disasters. To be fair to Excel, as you can see above, the defaults weren’t really that bad, given the limits of graphics cards in the day. Unfortunately, people got too excited about the 3d options.
Age 2: the Stephen Few fightback (2000-2010)
Stephen Few took on the spreadsheet behemoths in the first decade of this century. He made us all see sense and put science-backed best practice on the pedestal. People saw the light and visual tools began to ditch the dross in favour of charts that actually work.
Age 3: the creative years (2010-present)
The problem with Stephen Few’s approach is that people found his approach, well, boring. Unarguably his approach was functionally correct and just right for operational business dashboards. But many people were left unmoved. They found that following his approach didn’t engage people. As data journalism flourished and infographics exploded, there was a realization that a balance needed to be struck.
At the extreme end we found that people like David McCandless found success with their design-trumps-function approach but others, such as Alberto Cairo (see his Tapestry Conference slides) and Andy Kirk (8 hats) pushed the need to ENGAGE as well as INFORM.
Tell me your thoughts
My ideas are fluid around this. I’m trying to make the point that we’re in a great place with the combining fields of creative power and effective design. What else do I need to know?