Innovative Tableau

Chapter 36. How to Make Unit Histograms/Wilkinson Dot Plots

Unit histograms, or Wilkinson dot plots, show distributions of individual data points instead of bucketing them into bins like traditional histograms. My friend and Tableau Zen Master Hall of Famer, Steve Wexler, suggested this as an alternative to one of my visualizations, and I liked the idea so much that I wanted to show you how to build it in Tableau.

I show how to make one-dimensional unit charts in Tableau in Chapter 62 of Practical Tableau (O’Reilly, 2018), which are similar, but unit histograms are slightly more flexible because you can use a mark type other than bar (i.e., circle or shape). By the end of this chapter, you will be able to visualize a distribution of individual items which is effective and engaging. I also show you how to change the mark type so that the distribution looks like little men standing on top of one another’s heads which is, well, just for fun.

How to Stack Marks to Create Unit Histograms in Tableau

By the end of this chapter, you will be able to make a version of a dot plot that looks like this:

To create this type of chart in Tableau, your dataset must have the dimension members that make up the units on individual rows. To illustrate, I use the Order ID dimension from the Sample – Superstore dataset because every order has an individual row in the underlying data.

If ...