guidelines for graphing data erin e. barton. rationale visual inspection of graphed data is the...

Guidelines for Graphing Data

Erin E. Barton

Rationale

• Visual inspection of graphed data is the primary means by which data analysis occurs in SCR

• Graphs assist in communicating information quickly and without extensive transformation

Rationale

• Graphical displays of single-case data are very well-suited for online monitoring of the participant’s progress, by altering them every time new data become available, and for communicating results.

• Patterns are easily and quickly identified• Makes raw data transparent with minimal

transformation

Rationale

• Requires little training in mathematics and statistics – Simplicity often (but not always) is desirable

• Allows easy communication with others • Guards against accepting small effects

(theoretically)

Components• Origin• Abscissa—x axis• Abscissa label—almost always a time unit• Ordinate—y axis• Ordinate label—the value of the dependent measure• Scale break• Condition label—should be descriptive • Condition change lines• Phase change lines• Datum point, data points, data series, data path

Graphing Guidelines

1. Fair2. Objective3. Clear4. Without deception

Graphing Guidelines

1.Well-designed presentation 2.Complex ideas communicated with clarity,

precision, and efficiency3.More ideas in less time 4.Usually multiple variables displayed5.Extreme clarity: the truth about the data

(Tufte, 2001)

JABA Graphing Guidelines

1. Data points must be constructed of thin lines and be of sufficient size so that reduction will neither obscure their differentiation nor fill in such symbols as unfilled circles, triangles, and squares.

2. “Percentage of” should be used instead of “Percent of” when labeling the ordinate axis (“percent of” is grammatically incorrect).

JABA Graphing Guidelines

3. Avoid heavy lines for axes4. Provide scale marks along both axes at

sufficiently frequent intervals to permit x and y values of data points to be read accurately.

5.Be sure that axes meet at a right angle and that labels parallel their axes.

6.Align scale marks with labels and data points.

JABA Graphing Guidelines

7. Legends identify the data points within the figure.

8. Identify data paths with arrows and labels when possible.

9. Use text boxes only when space is not available for arrows and labels.

10.It is best to use all capital letters, but do not hesitate to use upper and lower cases when needed to fit in the area available.

Baseline Intervention Baseline Intervention

Components

Sessions

Verb

al T

arge

ts

Time Series: Abscissa or x-axis

Target Behaviors: Ordinate or y-axis Conditions

Condition change

lines

Baseline Intervention Baseline Intervention

Components

Sessions

Verb

al T

arge

ts

Time Series: Abscissa or x-axis

Target Behaviors: Ordinate or y-axis Conditions

Condition change

lines

Baseline Intervention

Participant 1

Participant 2

Participant 3Time Series: Abscissa or x-axis

Target Behaviors: Ordinate or y-axis

Conditions

Condition change

lines

Soci

al In

tera

ction

s

Days

0

2

4

6

8

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 200123456702468

101214

Baseline Intervention

Participant 1

Participant 2

Participant 3Soci

al In

tera

ction

s

Days

0

2

4

6

8

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 200123456702468

101214

Baseline Intervention

Participant 1

Participant 2

Participant 3Soci

al In

tera

ction

s

Days

-1

3

7

11

15

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20-113579

11131502468

101214

Baseline Intervention

Participant 1

Participant 2

Participant 3

ORDINATES MUST BE THE SAME

Soci

al In

tera

ction

s

Days

020406080

100

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 200

50

1000

20

40

60

80

100

Baseline Intervention

Participant 1

Participant 2

Participant 3

Pret

end

Play

Days

-1

3

7

11

15

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20-113579

11131502468

101214

Baseline Intervention

Participant 1

Participant 2

Participant 3Pret

end

Play

Days

ORDINATE SCALE SHOULD BE APPROPRIATE

(Kennedy, 1989)

0102030405060708090

100

Spo

ken

Wor

ds

Sessions

Baseline Intervention Baseline Intervention

02468

101214161820

Spo

ken

Wor

ds

Sessions

Baseline Intervention Baseline Intervention

ORDINATE SCALE SHOULD BE APPROPRIATE

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 2102468

101214161820

Spoken Words Challenging Behavior

Freq

uenc

y of

Chi

ld B

ehav

iors

Sessions

Baseline Intervention Baseline Intervention

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 2102468

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Spoken Words Challenging Behavior

Sessions

Baseline Intervention Baseline Intervention

USE DISTINCT, CLEAR MARKERS

Freq

uenc

y of

Chi

ld B

ehav

iors

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Peer Prompts Visuals

Days

Freq

uenc

y of

Soc

ial I

nter

actio

ns

Creating Alternating Treatment Design Graphs

1 2 3 4 5 6 7 8 9 10 11 1202468

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Peer Prompts Visuals

Days

Freq

uenc

y of

Soc

ial I

nter

actio

ns

The default will be to have gaps….

1 2 3 4 5 6 7 8 9 10 11 1202468

101214161820

Peer Prompts Visuals

Days

Freq

uenc

y of

Soc

ial I

nter

actio

ns

….or to plot the days without data as zero.

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Peer Prompts Visuals

Days

Freq

uenc

y of

Soc

ial I

nter

actio

ns

Resulting Alternating Treatment Design Graphs

Practice

ABABBaseline 1: B1: (0, 0, 0, 0, 0) B2: (10, 13, 15, 10, 11)Intervention 1: B1: (4, 7, 2, 8, 10, 12) B2: (1, 3, 5, 1, 1, 0)Baseline 2: B1: (4, 1, 2, 3, 0) B2: (5, 13, 10, 9, 15)Intervention 1: B1: (8, 6, 9, 10, 12) B2: (0, 1, 0, 1, 1)

0

2

4

6

8

10

12

14

Target Behavior Challenging Behavior

Freq

uenc

y

Sessions

Baseline Intervention Baseline Intervention

Review

• Ensure all components are clearly identified

• Ordinates must be the same • Scales should be appropriate• Use distinct markers• Separate conditions

References Barton, E. E. & Reichow, B. (2012). Guidelines for graphing data with Microsoft PowerPoint for Office 2007. Journal of Early Intervention, 34, 129-150.

Dixon, M. R., Jackson, J. W., Small, S. L., Horner-King, M. J., Mui Ker Lik, N., Garcia, Y., & Rosales, R. (2007). Creating single-subject design graphs in Microsoft Excel. Journal of Applied Behavior Analysis, 42, 277-293.

Wolery, M., Dunlap, G., & Ledford, J. R. (2011). Single-case experimental methods: Suggestions for reporting. Journal of Early Intervention, 33, 103-109.