Head-n-Tail Analysis (Part 1): The Toolkit

[Head-n-Tail Analysis (Part 2): 30 sec to Dashboard]

What is head-n-tail analysis? It consists of top ranking and tail aggregation.

Recently I have had a few different analysis cases which can all use the same simple yet powerful methodology. It seems quite a fundamental analysis that can be applied widely.

Given a group of salesmen, stores or league teams and the sales, profit or revenue they each made, we are always interested in knowing
- the top performers (Head)
- the performance of the rest (Tail)

For the tail, we will just give the aggregate result. And I would call it Head-'n'-Tail analysis. (Let me know if you can suggest a better name) It is a mix of both ranking and aggregation. The interesting part of this analysis is, it not only gives us the top performers but also the aggregation view of the tail.

Similar to Pareto analysis, it's important to know that 20% of the salesmen make up 80% of the sales. It's just as interesting to know that the other 80% of salesmen make only 20% of the sales. Moreover, this Head & Tail analysis tells who the top guys are.

I will present here a simple and quick toolkit for the analysis. I assume that the data set has got 2 columns: one dimension and one measure.

The Head-n-Tail analysis toolkit consists of 3 elements, all having both head and tail:
- Ranking
- Pareto analysis
- Pie chart

The tail size is adjustable to be short or long.

The difference the toolkit makes relative to traditional approach is
- Ranking includes the comparison of top guys and the aggregation view of the rest of the group.
- It keeps the running percentage details for the top guys and aggregates the rest together
- Pie chart used to be messy with too many slices. The new one will only show a few if you wish.
- A knob is provided for you to adjust the size of head or tail for your analytic pleasure.

As an example, we analyze the TV revenue for the English Premiere League teams in 2012-13. From the following charts, we see
- the top 5 teams and their respective revue (in million euros), and the aggregate revenue of the rest.
- the running % of total league revenue of the top teams and the rest
- the visual pie share of top teams and the rest

In the next part, I will show how you can create a Head-n-Tail analysis dashboard in 30 seconds, based on the above toolkit.

(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