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.