Category: Visualization

I continue my dashboard visualization series with a bit of an extended rant:

The best use of a pie chart is to show a simple share of a static total.  Here, we can see that Daredevil has almost half of the critics’ reviews, and that The Punisher and Jessica Jones are split.

This simple pie chart also shows some of the problems of pie charts.  The biggest issue is that people have trouble with angle, making it hard to distinguish relative slices.  For example, is Jessica Jones’s slice larger or is The Punisher’s?  It’s really hard to tell in this case, and if that difference is significant, you’re making life harder for your viewers.

Second, as slice percentages get smaller, it becomes harder to differentiate slices.  In this case, we can see all three pretty clearly, but if we start getting 1% or 2% slices, they end up as slivers on the pie, making it hard to distinguish one slice from another.

Third, pie charts usually require one color per slice.  This can lead to an explosion of color usage.  Aside from potential risks of using colors which in concert are not CVD-friendly, adding all of these colors has yet another unintended consequence.  If you use the same color in two different pie charts to mean different things, you can confuse people, as they will associate color with some category, and so if they see the same color twice, they will implicitly assign both things the same category.  That leads to confusion.  Yes, careful reading of your legend dissuades people of that notion, but by the time they see the legend, they’ve already implicitly mapped out what this color represents.

Fourth, pie charts often require legends, which increases eye scanning.

Click through to read me complain about other types of visuals, too.

I continue my series on dashboard visualization by looking at pictures:

In a bit more detail, you can make a dashboard glanceable by following these guidelines:

1. Ensure that there is clear purpose in your metric design and display.  In other words, think about which metrics you want to show, how you want to show them, and where you put metrics in relation to one another.

2. Group metrics by function into sections.  Look at the dashboard above.  It has four clusters of metrics:  those around revenue, new customers, revenue per customer, and customer acquisition cost.  All of the revenue metrics are clustered in the top-left quadrant of the dashboard.  Furthermore, all revenue-related metrics (that is, revenue metrics and revenue per customer metrics) are on the left-hand side of the dashboard, so the CEO can focus on that half and learn about revenue and revenue per customer.  She doesn’t need to look in the top-left corner for one revenue measure and in the bottom right for another; she can focus down to a portion of the dashboard and get an answer.

3. It should be easy to see and differentiate those clusters of metrics.  Our natural instinct might be to put borders around the clusters, but whitespace is your friend—remember, less is more.  If you add a bit more whitespace between clusters of measures, you’ll make it easy for people to see that there’s a difference without distracting them with unnecessary lines.

I cover the Rule of Thirds, Glanceability, and Color Vision Deficiency, three important considerations for a designer.

I have a post looking at three visual principles important to creating good dashboards:

In European languages, we read from left to right and from top to bottom.  In Middle Eastern languages like Hebrew and Arabic, we read from right to left and top to bottom.  In ancient Asian languages (particularly Chinese), we read from top to bottom and right to left, but in modern Chinese, we read left to right and top to bottom.  As far as Japanese goes, we read every which way because YOLO.  The way we read biases the way we look at things.

There has been quite a bit of research done on looking at where we look on a screen or on a page. I’m going to describe a few layouts, but focusing on research done on Europeans.  If you poll a group of Israeli or Saudi Arabian readers, flip the results.

Read the whole thing.  The second part of that comes out soon.

I continue my series on dashboard visualization:

Before you build a dashboard, you have to know your audience.  If you don’t know who your viewers will be and where their interests lie, you run the risk of building a dashboard which fails to serve their needs.  When that happens, people stop looking at your dashboard.  In order to increase the likelihood that your dashboard will be useful, I have a few critical questions:

1. Who is your intended audience?
2. How will your intended audience use your dashboard?
3. What actions do you want them to take as a result of what they see?
4. Are you showing the right measures in the right way?
5. What cultural differences might matter?

The rest of this post will drill into each of these concepts.

These are the types of questions which can make the difference between a dashboard people love and a dashboard people never use.

I’ve started a new series on data visualization:

There are a few things which make dashboards useful:

• Ideally, the dashboard is a “single pane of glass.”  By that, I mean that all relevant indicators are visible on the screen at the same time.  With my car, it’s close but no cigar:  I can see one of miles traveled, average fuel mileage, or current fuel mileage at a time.  If I want to see a different item, I need to hit a button on the steering wheel to scroll through those options.  By contrast, the TV show dashboard has everything on a single screen with no scrolling or switching required.

• Key Performance Indicators (KPIs) are readily apparent.  For the TV show dashboard, we have a couple key metrics on display:  episode rating and number of votes as sourced from IMDB at the time I pulled those numbers.

• Relevant KPIs are bunched together in a logical fashion.  On the top half of the dashboard, we see two visuals relating to average rating by show.  The bottom half show rating & user vote counts for the three highest-rated shows.

• Layouts are consistent between dashboard elements and between related dashboards.  On the TV show dashboard, bars and columns use a single, consistent color.  Also, shows have thematic colors:  Daredevil in red, Jessica Jones blue, Punisher black, etc.  If I had a second dashboard for season two, I would want to use the same theme.

Read on for more details about what a dashboard is and some of the sundry forms of dashboards.