Misleading Data Visualizations

Question 1

Why can graphs be tricky business according to Yang?

Answer 1

Graphs do not have to be factually wrong to mislead

Question 2

How does the model of display comprehension looks like?

Answer 2

look at it in the summary and memorize!!!

Question 3

What part of the model of display comprehension can you influence as a visual designer?

Answer 3

The external display part

Question 4

What should graphs follow?

Answer 4

Design principles

Question 5

What is the No. 1 principle?

Answer 5

You first have to take a look at what is my goal with this visualization. One goal can be visual pleasure

Question 6

What did the study by Bateman et al. researched?

Answer 6

They researched what the cognitive effect was of two types of visualizations (an really graphic one graph, lady’s leg and a simple graph).

Banished? vs. basic

Question 7

What is the conclusion of the research by Bateman et al.?

Answer 7

The understanding of the display is the same in both visualizations. But if your goal is to please people aesthetically, then they find that banished graphs are indeed more attractive, and easier to remember.

Question 8

What does Tufte argues?

Answer 8

That using enbanishments is actually chart junk. Chart junk are somehow misleading according to him, it could distract the audience.

Question 9

What is the data-ink ratio ?

Answer 9

Minimalist principles, most notably.

Most - if not all - ink should be used to present relevant information. Ink spent on other things than relevant information is ‘chart junk’, which is of no interest of the viewer.

Question 10

What are the four principles by Hegratry about how graphics convey meaning?

Answer 10

1. The relevance principle
2. The apprehension principle
3. The salience principle
4. the principle of capacity limitations

Question 11

What is the relevance principle in how graphics convey meaning?

Answer 11

Graphics should present no more or no less information than is needed.

Question 12

What is the apprehension principle in how graphics convey meaning?

Answer 12

To be effective, a visual display has to be accurately perceived

Question 13

What is the salience principle in how graphics convey meaning?

Answer 13

Design displays to make the most important thematic information salient

Question 14

What is the principle of capacity limitations in how graphics convey meaning?

Answer 14

Displays should be designed to take account of limitations in working memory and attention.

Question 15

What is the lie factor formula?

Answer 15

Size of effects shown in the graphic / size of effect in data

Question 16

How should you interpret the lie factor?

Answer 16

So the closer the lie factor to 1.0, the more accurate the graphic is

Question 17

What is the size of effect formula?

Answer 17

second value - first value / first value

Question 18

Who is the liar according to Cairo?

Answer 18

Charts, graphs, maps, and diagrams do not lie. People who design graphics do.

Question 19

What is a ‘lie’ according to the literature about ethics?

Answer 19

” A lie is an intentionally deceptive message in form of a statement”

So, visualizations can mislead, not lie. People lie.

Question 20

On what three strategies are most lies based?

Answer 20

1. Hiding relevant data to highlight what benefits the sender
2. Displaying too much data to obscure reality
3. Using graphic forms in inappropriate ways (i.e., distorting data)

Question 21

What is the subjective comparison task?

Answer 21

• You will be presented with two graphs in a row
• For every graph, compare the upper left bar with the upper right bar. After doing his, indicate whether you find the difference between the bars

Question 22

What was the conclusion is the subjective comparison task?

Answer 22

The depicted data is exactly the same

only the representation, in terms of the y-axis are different.

Question 23

What is the truncation effect?

Answer 23

Graphs as misinformation.

y-axis not starting at 0

Question 24

What is the truncation effect with experiment 1 of Yang et al. ?

Answer 24

The effect was consistent for all participants

Question 25

What is the truncation effect for experiment 2 of Yang et al.?

Answer 25

The truncation effect and explicit explanation for all participants –> so a warning, that the graphs might be misleading.

Effect = consistent for 85% of all participants

Question 26

What is the truncation effect of experiment 3 of Yang et al.?

Answer 26

The truncation effect and explicit warning (manipulated).

Effect = 84% all participants

Same findings, people still didn’t understand what was going on with the truncation.

Question 27

What is the truncation effect of experiment 4 of Yang et al.?

Answer 27

Truncation effect, explicit warning (manipulated), and 1-day delay.

Effect = consistent for 88,5% (day 0) and 85,4% (day 1) of all participants

Question 28

What is the truncation effect of experiment 5 of Yang et al.?

Answer 28

Truncation effect, explicit warning (manipulated), and expertise.
They used Phd students that work with a lot of quantitative data and phd students in humanities which do not use quantitative data.

Effect = consistent for 78,2% (day 0) and 75,2% (day 1) of all participants

Question 29

What are the challenges of data visualizations according to Cairo?

Answer 29

• Stories and visuals originate from ‘high authorities’ - companies, governments, etc.
• Many (journalists) people are not trained in the scientific method, research techniques, and data
• Many (journalists) people lack a “bullshit detector”
• (journalists) people make mistakes that fall into categories that exactly match those of lies.