Dr Eugene F.M. O’Loughlin

National College of Ireland

Data Visualization

What Can You See?

Agenda

History Lesson

The Democratization of Data

Making Sense of Data

New Challenges to Big Data

Visualization

Data Presentation

Data Visualization tools

Short Exercise

Data Visualization - 1786

Source: Commercial and Political Atlas (Playfair, 1786)

Charles Joseph Minard (1869)

Image source: Wikimedia Commons.

Broad Street

Pump (source of

contaminated water)

London Cholera Epidemic

Clusters (Snow, 1854)Im

age s

ourc

e: W

ikim

edia

Com

mons.

Today – YouTube Analytics

www.youtube.com/eoloughlin

Drill down…

Definition of Data Visualization

(Kirk, 2016)

Why is data visualization

important?

(sas.com) Because of the way the human brain

processes information, using charts or graphs to visualize large amounts of complex data is easier than poring over spreadsheets or reports

Image source: https://projectyourself.com/wp-content/uploads/sites/4/2014/08/Depositphotos_10171240_l.jpg

Top Down Processing Theory

Psychologist Richard

Gregory (1970) argued that

perception is a constructive

process which relies on top-

down processing

Stimulus information from

our environment is frequently

ambiguous Gregory, R. (1970). The Intelligent Eye. London: Weidenfeld and Nicolson.

Perceptions can be

ambiguous

The Necker Cube

Non-realizable Objects

Four ≠ Three

What do

you see?

The Democratization of Data

Employees who aren’t data scientists or analysts should be able to:

◦ ask questions of the data based on their own business expertise

◦ quickly and easily find patterns

◦ spot inconsistencies

◦ get answers to questions they haven’t yet thought to ask

“Small” Data – Easy!

New challenges to data

visualization

Image source: https://thombartley.wordpress.com/2014/05/08/big-social-vs-little-social/

Visualizing Big Data

Big data brings new challenges to visualization:◦ Speed of data

◦ Size of Data

◦ Diversity of data

◦ Cardinality

Move beyond comfort zone because of:◦ Volume

◦ Variety

◦ Velocity

Image source: https://rc.fas.harvard.edu/how-big-is-big-data/

Big Data - Value

One of the major challenges of big data is how to extract value from it

We know how to ◦ create it

◦ store it

But we fall short when it comes to ◦ analysis

◦ synthesis

Visualizing Big Data

Handling large volumes

Visualizing Big Data

Correlation Matrix

Visualizing Big Data

Time Series/Forecasting

Visualizing Big Data

Sankey Diagram

Visualizing Big Data

Fun & Challenging!

However…◦ Wrong visualization?

◦ Audience?

◦ Consider more than one visual?

Important◦ How do viewers

process visual information?

◦ Do you understand the composition and relationships in your data?

Poor Data

Visualization

AheadImage source: http://www.clipartbro.com/clipart-image/warnign-sign-clipart-26760

Data Presentation

To derive understanding from data we need to see it represented in a different, visual form

Anatomy of a chart:

◦ Marks Points

Lines

Areas

◦ Attributes Size

Colour

Position

Image source: http://www.pngmart.com/image/tag/lionel-messi

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Lional Messi: Games and Goals for FC Barcelona

Appearances

Facilitating Understanding

The Three Stages of

Understanding

Perceiving Interpreting Comprehending

What does it show?

Where is big, medium,

small?

How do things compare?

What relationships exist?

What does it mean?

What is good and bad?

Is it meaningful or

insignificant?

Unusual or expected

What does it mean to me?

Where are the main

messages?

What have I learnt?

Any actions to take?

Kirk (2016)

Importance of Context

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10

20

30

40

50

60

Lional Messi: Games and Goals for FC Barcelona

Appearances

0

10

20

30

40

50

60

Total Sightings of Winglets and Spungles

Winglets

Will it Make the Boat go

Faster?• Focus on performance

Great Britain Men’s Eight Rowing Team

(Sydney Olympics, 2012)

Images sourced: http://www.willitmaketheboatgofaster.com

Good Design (Andy Kirk,

2016)

The Three Principles of Good

Visualization Design

Principle 1

Good data

visualization is

TRUSTWORTHY

Principle 2

Good data

visualization is

ACCESSIBLE

Principle 3

Good data

visualization is

ELEGANT

Fragility of Trust (Figure-ground Perception)

Image source: Business Insider. Image source: Business Insider.

Principle 1

Good data

visualization is

TRUSTWORTHY

Reward vs Effort

Effort

◦ Act of understanding

Reward

◦ Achieving of understanding

You can’t force viewers to

understand (but you can smooth

the way)

Know your audience

Principle 2

Good data

visualization is

ACCESSIBLE

Elegant Design

How do you achieve elegance in design?

◦ Eliminate the arbitrary

◦ Thoroughness

◦ Style

◦ Decoration should be additive, not negative

Principle 3

Good data

visualization is

ELEGANT

Image source: Wall Street Journal.

If you're

explaining,

you're losing.The Reagan Diaries (2007)

Image source: https://en.wikipedia.org/wiki/Ronald_Reagan

Image source: https://en.wikipedia.org/wiki/United_States_presidential_election,_1984

Data Visualization Tools

Exercise: Data Visualization

Find all possible ways to visualize a (ludicrously) small data set of just two numbers

75

37

Questions