PRINCIPLES OF GOOD DATA VIZ AND STORYTELLING

ANA-MARIA MOCANU

DATA SCIENTIST, KANTAR INSIGHT

1. KNOW YOUR AUDIENCE

Exec team?

Finance team?

Dev team?

2. KNOW WHAT TO AVOID

What's my favourite data task?

Data viz

Machinelearning

Text Analytics

Dataintegration

Communication

Data cleaning

Data viz Machine learning

Text Analytics Data integration

Communication Data cleaning

Data viz

Machine learning

Text Analytics

Data integration

Communication

Data cleaning

0% 10% 20% 30% 40%

3. KNOW THE DATA INSIDE OUT

• Visuals are much easier once the underlying data model is robust and correct

• Know differences between Counts vs. Distinct counts; Left join vs. Inner join

• Understand how you want to slice the data early on

• If you need to use assumptions in the data, validate them and keep them in mind throughout the way

• Always check the results of the visualisation!

4. KEEP IT CLEAN AND SIMPLE (IT’S MORE DIFFICULT THAN IT SOUNDS)

• Don’t overcomplicate dashboards - great stories can be told with simple KPIs and charts

• Limit yourself to answering max. 3 questions in your project. Examples can be:

• Where are your users coming from?

• Which activities are contributing to the highest ROI ? Where are you making the most impact?

• Where are you losing out? Where can you do better?

• Who is your competition and how are they doing?

5. A DATA STORY CAN BE TOLD IN MANY WAYSNumber of U.S. soldiers killed in the Iraq war from 2003 to 2017*

*Source: https://www.statista.com/statistics/263798/american-soldiers-killed-in-iraq/

6. USE CHART FEATURES – COLOUR, SIZE AND SHAPE

Colour: Sentiment (from extremely fun

to plain boring/ not helpful)

X-axis: Amount of knowledge gained

Y-axis: Level of contribution to my

career

We can add different shapes and

sizes to analyse other variables (e.g.

number of hours spent)

7. USE CHART TYPES

*Source: https://plot.ly/r/sankey-diagram/

There are many chart types in the

world. Sankey diagrams are good for

visualising flows, mosaic charts are

good for categories etc.

Don’t forget Principle 4 – Keep it

clean and simple

8. USE YOUR IMAGINATION

• Bring in an

additional dataset

• Create a chart no

one saw before

• Find something funny

in the data that’s

worth telling

*Source:

http://www.tylervigen.co

m/spurious-correlations

For example, how to educate that correlation does not imply causation:

9. REACH OUT FOR HELP

• Ask your end users for their opinion. Show your dashboard to someone creative. Or someone who

has no idea what’s going on – do they understand your story?

• Most of the visualisation tools have forums you can reach out. Have a regular look.

• Also, keep an eye on things like “Viz of the day” and media reports and infographics.

SO, IN SUMMARY:

1. Know your audience

2. Know what to avoid

3. Know the data inside out

4. Keep it clean and simple

5. Choose how you want to tell the story – It can be told in many ways

6. Use chart features

7. Use chart types

8. Use your imagination

9. Reach out for help

“NUMBERS HAVE AN IMPORTANT STORY TO TELL. THEY RELY ON YOU TO GIVE THEM A CLEAR AND CONVINCING

VOICE.”

STEPHEN FEW

ANA-MARIA.MOCANU@KANTAR.COM