Tableau activity
Data visualisation with Tableau
Tableau
is a powerful and flexible data visualisation tool.
Before you start
Before doing this activity you will need to install Tableau onto your computer. Tableau Public is already installed on the student-use computers at Griffith. If you are using your own computer, follow the instructions below to install Tableau.
- Download the sample data: Queensland Hospital Procedures 2018
- Launch Tableau
- Click ‘Connect to data source’
- Select the sample data from your Downloads folder
- Click OK
The data should appear in columns on the bottom half of your screen.
Prepare your data for use
You will see that Tableau attempts to detect what kind of value is in each column and assigns a value type accordingly. Tableau doesn’t get all of these guesses correct, so we have to correct some of them.
- Click on the ‘Abc’ at the top of the ‘Percent on time’ column
- Select ‘Number (decimal)’ from the list
- Do the same with ‘YoY Variation’, ‘Percent ready within time’
- Click on the ‘Abc’ at the top of ‘Date updated’
- Select ‘Date and time’ from the list
The data should appear in columns on the bottom half of your screen.
Now watch the video below which will take you through the next few stages of the activity.
Make your first chart
You will start to see the power of Tableau very quickly when you move to the Worksheet.
Click on ‘Sheet 1’ at the bottom of the window. You will see that your columns have been placed in two categories, dimensions
and measures
.
- Drag the dimension
Hospital name
to theRows
field at the top of the Worksheet - Drag
Number treated
from the Measures list to theColumns
field at the top of the worksheet.
Voilà! You have your first chart!
Add filters
Oh-oh! There’s a problem. One of the bars is far larger than the others, and it’s not just that one hospital has been much more efficient than all the others.
There is an entry called Queensland Reporting Hospitals
which records the sum of all the other entries. This is distorting the chart so we need to remove it.
- Drag
Hospital name
from the Dimensions List to theFilters
box - Scroll down and uncheck the box next to
Queensland Reporting Hospitals
- Click OK
There’s one more filter we need to add. In the ‘Urgency’ field, there is also a summary row that is distorting the data. So let’s do it again for Urgency.
- Drag
Urgency
from the Dimensions List to theFilters
box - Scroll down and uncheck the box next to
ALL
. Make sure the others are checked. - Click OK
Sort and colour
It’s time to make it look a bit nicer.
- Click the
Sort descending
button on the toolbar. - Drag
Number treated
from the Measures list to theColor
box under the heading ‘Marks’ - Click the
Color
button - Click
Edit colors
- Select a palette from the
Palette
drop-down. I chose ‘Red-Green Diverging’
Try playing around with a few more of the charts in the ‘Show me’ palette, or dragging different dimensions and measures into the Row and Column fields. You can even drop more than one measure into one of the fields, for a multivariate chart.