Graphics that present data
Quick review
1. Show the reader what s/he needs to see.
2. Plan the sequence and directionality.
3.Think about the focal point of the graphic.
4. Integrate labels, units of measurement, and information
into graphic to make interpretation efficient.
5. Make the color work with the information.
6. Place graphic where it will improve reader’s
comprehension of complex material.
7. Label and title all graphics.
8. Remember to edit, revise, and proofread graphics.
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Astronautics
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And, with graphics that present data. . . 10. Don’t distort or disguise data.
- Choose the appropriate graphic.
- Label important events in data.
- Be precise about data points.
- Be sure to show error variance.
- Avoid 3-D graphics, false perspectives, and
“chart junk.”
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Astronautics
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Effective tables
• Order items in a way
that your viewer finds
useful.
• Label columns and
rows clearly and
specifically.
• Align entries. (In
budgets, line up on
decimal.)
• In large table, use
white space or
horizontal rule as a
guide.
• Follow conventions for
labeling and
displaying graphics.
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Astronautics
4
What works well? What doesn’t work?
Table 3: Sources of error in aerodynamic testing.
Error Source
Type of Error
Relative Magnitude
Wall interference
Systematic
Large
Mount interference
Systematic
Large
Load cell accuracy
Random
Small
Load cell noise
Random
Small
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Astronautics
5
Effective bar charts
• Decide if chart should
display vertically or horizontally.
• Use tick marks to
indicate quantities on
axis parallel to bar.
• Integrate label on or
next to bar except if it
would be too
confusing.
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Astronautics
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100
80
East
West
South
% Correct
90
80
70
60
50
40
30
20
10
0
60
40
20
1st
2nd
3rd
4th
Qtr
Qtr
Qtr
Qtr
0
Analog
PT
Rankine
Display
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Astronautics
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Effective line charts
• Use tick marks to
indicate quantities.
• Start axes at zero
unless there is a good
reason not to. Then, be
scrupulous about
indicating this.
• Consider labeling data
points.
• Label accurately.
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Astronautics
8
Dog Food Sales
Yum-E-Dog
Yuk-E-Dog
$25,000.00
$20,000.00
$15,000.00
$10,000.00
$5,000.00
$Jan
Feb Mar
Apr
May
Jun
Jul
Aug Sep
Oct
Nov Dec
Courtesy M. Anderberg
Department of Aeronautics and
Astronautics
9
Effective pie charts
• Label each edge and
give its percentage of
whole.
• Limit number of
wedges.
• Avoid 3-D.
• Use color carefully.
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Astronautics
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Human
Resources
21%
Physical
Resources
39%
General
Government
10%
Current Military
17%
Past Military
13%
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Astronautics
11
Effective scatter plots
• Organize nontemporal data.
• Show correlation between two variables.
100
90
80
3
5
2
6
7
1
2
7
1
7
80
90
75
80
90
50
65
85
40
100
Regents Score
Study Hours Regents Score
70
60
50
40
30
20
10
0
0
1
2
3
4
5
6
7
8
Hours of Study
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Astronautics
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