Correlation Calculations in Tableau

There are more than one ways to calculate correlation between two series/vectors in Tableau.

1.Correlation via TabPy

I did this because I would like to know how to set up the new Python extension: TabPy.

In Tableau 10.1, we can take advantage of TabPy. Alexander Loth has written a nice tutorial here. If you don't have GIT installed in your computer, you can just go to http://github.com/tableau/TabPy and download the package.

Unpack the zip file and extract the "TabPy-master" folder. Follow the steps to install TabPy. It may take some time to install but the process is smooth. It took me 30 min or so. But it may depend on network and computer.

Use the script in the calculated field to calculate the correlation. His twbx file is no longer downloadable. I reproduced the file according to the image in the tutorial. Here is the file for you to download.

2.Correlation via Window_Corr()

In Tableau 10.2, there is a new function Window_Corr() which calculates the correlation between two vectors of aggregated measures.

By using the new function, I got exactly the same result as the one via TabPy. The window function has to compute along the "Customer Name" dimension.

This example is included in the same file.

Postscript

The one with TabPy can't be published to Tableau Public website because it doesn't support Python or R extension. Tableau Public desktop neither.

Note that there is a Corr() function which is for calculating the correlation between two non-aggregated values.

Hope this helps.

(Refresh the page if you want to view the gif image multiple times. Or go to Tableau Public and click the button at the top-right corner.)

Jake and I collaborated on a dashboard. He told me that he learnt a way to create an in-place help page in Tableau. He first saw it at a conference somewhere and couldn't recall who the speaker was. So I am blogging here about it but the credit goes to somebody else. If anyone knows who the original creator is, leave a comment below.

The key idea is to float a semi transparent worksheet on top of the dashboard, where a help text box is strategically placed on top of each chart. This way, we can explain how to view each chart and what data points are important, etc. This worksheet is collapsible by a show/hide button.

Below I would like to show how this worksheet can be constructed.

1. Sheet with a single data mark.

Double click the empty space in Marks panel and add two single quotes. Make the null pill a text label. This creates a single null mark.
Set the view as "Entire View"

2. Create an show/hide button

Go to the target dashboard
Drag a floating vertical container to the dashboard, making it cover all the area of interest.
Drag the Single Null Mark sheet and drop it into the above container. Hide the sheet title.
Create an open/close button for the container and place the button at the top-right corner.

3. Add annotations

Format the sheet background opacity as 70% in the layout manager
Select area annotations and place them anywhere of interest.
Write help text and format it to highlight important messages.
The text can serve as functional guide and/or insight guide.

Here is an example. Feel free to download the workbook and explore. Click the "i" button at the top-right corner to view the in-place help.

Add a comment

Vizible Difference

In search of data visualization excellence

1. Sheet with a single data mark.

2. Create an show/hide button

3. Add annotations

Add a comment