Dashboarding concentrates on representing data in a small space while still getting across key concepts in the data. It is important to use the space effectively. There should be a balance between representing too much information and representing not enough information.
Some people circumvent the issue altogether by avoiding data visualization or perhaps simply not requiring it for their roles. For example, you might run up against individuals who are not interested in the "pretty pictures" and want to see the numbers. How do you combine this requirement with other people's requirements to have a visual representation of the data?
Fortunately, there are a number of ways in which we can use data visualization techniques to convey the message of the data in a table. In itself, a table is a valid data visualization technique because tables are very good at representing detail. In particular environments, such as finance, it is the minute details within the table that make all the difference.
In data visualization, we also have to cater to the people who just want the numbers as well as those who have a more visual requirement.
In this recipe, we will create a crosstab that has a custom calculation in it, which allows us to enhance the representation of the data for those who prefer a more visual approach; in addition to this, we'll also provision numbers for those who simply want a table.
In this example, we will use the calculation Index()
. This ranks members depending on their value. We can use the ranking calculation in order to restrict our data visualization so that it only shows the top three best performers. This is a concept that is key to many dashboards, and we will look at implementing this element in this recipe.
We will continue to work on the Tableau Chapter 2
workbook and start a new sheet by selecting Ctrl + M.
Chapter 2
workbook and duplicate the worksheet called Using Crosstabs Flexibly. Rename it to Custom Calculations
.Rank
and then right-click on it to see a pop-up menu. Select the option called Create Calculated Field. You can see an example in the following screenshot:Rank
, click on it and choose Edit.Sales Ranking
in the Name field.Index()
in the Formula field.Index()
in, click on OK and you are returned to the main Tableau interface.Now, let's take the scenario in which we want to display only the top three performers by region.
Make sure you enter the number 3
on the right-hand side rather than 6
. Although there are six options, this filter means that Tableau will only display the top three best-selling regions.
You can see the final data visualization in the following screenshot:
Tableau offers us many interesting ways to compact the data down to its minimum design while still helping us to show the message of the data. Although the main visualization is very small, it helps us to use this element in a later dashboard because we have packaged a lot of information into a very small space.
The visualization shows the following:
To summarize, making data tell a story is a challenge, particularly when there is not much space to play with. However, making data tell a story is fun with Tableau.