May 14, 2012

How common is your birthday? Find out exactly with an interactive heat map.

Matt Stiles posted a heat map on his blog yesterday that I thought was pretty well done.  I decided to get the data from and recreate it in Tableau.

It takes under 20 seconds and under 10 clicks to create it in Tableau, more like 15 seconds if you’ve been using Tableau longer.

Matt chose a brownish color palette, but I wanted to try lots of different colors.  Tableau makes is incredibly simple to try out many options very quickly.  I tested green, blue, gray and orange-blue palettes before settling on an orange palette.  For my eye, the orange palette made distinguishing the colors easiest.

Creating this as an interactive viz in Tableau allows you to provide the reader/viewer/interactor with more information.  Hover over your birthday and you will see exactly where it ranks.  Try it! 

In a static version, you’re left to guess at the approximate range in which it falls.

Check out Matt’s post and the comments.  There are some interesting insights from the readers including:

  • Matt struggled with getting the colors just right using Illustrator.  With Tableau, it’s all built in.  There’s no need to tinker.
  • Doctors apparently don’t like having their vacations disturbed.  Check out how around major holidays (July 4th, Thanksgiving, Christmas) there a fewer babies born.
  • September clearly has many of the top days (in fact it has all of the top 10), but July and August aren’t far behind.  It looks like people conceive during all of those Thanksgiving, Christmas and New Year’s parties.
  • A reader noted that the 13th seems to be least common on average.  Perhaps that’s because many people see that as an unlucky day.