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Chapter 6 – Making and Interpreting Graphs in Single-

Subject Research

Ps534

Dr. Ken Reeve

Caldwell College

Post-Bac Program in ABA

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Review…

EXPERIMENTAL CONTROL = demonstration of functional relationship between IV and DV

EXPERIMENTAL CONTROL = is the evidence for inferring we have high INTERNAL VALIDITY

EXPERIMENTAL CONTROL = is the evidence for inferring we have low or no threats from confounds

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Review…

DATA = collection of observations (measurement) of TARGET BEHAVIOR (DEPENDENT VARIABLE)

And.. DATA = collection of observations

(measurement) of METHODS TO CHANGE BEHAVIOR (INTERVENTION or INDEPENDENT VARIABLE

DATA = needed to infer that you have a FUNCTIONAL RELATIONSHIP

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GRAPHS

Visual format for depicting data In S-S research, allows us to see ONGOING

progress of data Allows us to immediately see changes as a result

of interventions (sometimes as happy accidents!) Simpler than stats for inferring differences! Relies on CLINICAL (EDUCATIONAL)

SIGNIFICANCE before findings are accepted as valid

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LINE GRAPHS: nuts and bolts LINE GRAPH (FREQUENCY POLYGON) =

most frequently used graph in ABA

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LINE GRAPHS: nuts and bolts

LINE GRAPH (FREQUENCY POLYGON) = Shows quantifiable change in DV (target behavior) as a function of time passage OR condition/treatment change (IV)

Measurement scale of DV is on Y axis (ordinate)

Measurement of time or condition change is on X axis (abscissa)

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LINE GRAPHS: nuts and bolts

PHASE CHANGE (CONDITION CHANGE) LINES

Used to indicate that IV is being manipulated

In other words, treatment is being presented, or withdrawn

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LINE GRAPHS: nuts and bolts

DATA POINTS Used to indicate

quantity of measurement and WHEN measurement was taken

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LINE GRAPHS: nuts and bolts

DATA PATH Is the line

connecting data points

A/k/a RESPONSE CURVE

A/k/a the graph’s FUNCTION

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LINE GRAPHS: nuts and bolts FIGURE LEGEND (not shown here but it is a

summary of what the graph shows)

Ex. “Percentage of training and probe trials in which each child produced a correct helping response, plotted as a function of condition across consecutive sessions. Training trials are represented by the closed circles and probe trials by the open circles.”

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LINE GRAPHS: nuts and bolts FIGURE KEY =

Identifies type of data point

LABELS = identifies participants, conditions, and any historical variables

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BAR GRAPHS: nuts and bolts BAR GRAPH

(HISTOGRAM) = usually used to summarize data

Always presented AFTER line graphs!

Points are not connected because each label on X axis is a discrete category and not a continuous dimension

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CUMULATIVE RECORD GRAPHS: nuts and bolts

Shows accumulation of occurrences of DV over time

Cannot ever decrease in value!

Note that “no behavior occurring” would be shown as a flat line!

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CAUTION! The next type of graph we’ll discuss is often VERY

CONFUSING to most folks What we’ve seen so far is measures of ACTUAL

change in target behavior (ex. 2/10 questions answered correctly vs. 4/10 questions answered correctly)

The difference from one tick mark to another on the Y axis is always the same amount (see next)

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CAUTION! BUT if the scale on the Y axis used by different

researchers is different as seen below, then it is confusing as to whether progress is occurring

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CAUTION! And…sometimes we don’t want to measure

the actual amount of change in DV Instead we want to measure a RELATIVE or

PROPORTIONAL CHANGE Anyone lost yet? (see next)

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CAUTION! What is RELATIVE or PROPORTIONAL

CHANGE? ACTUAL change in target behavior (ex. 2/10

questions answered correctly vs. 4/10 questions answered correctly) is an increase of 2 questions correct

RELATIVE or PROPORTIONAL CHANGE in this case is an increase of DOUBLE (TWICE AS GOOD AS BEFORE)

Still lost? (see next)

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CAUTION! Why would we ever measure RELATIVE or

PROPORTIONAL CHANGE instead of actual change?

Sometimes we want to see the DV increase by some proportional measure each time we apply treatment. For example, we may want behavior to increase by 10x after every training session

Still lost? (see next)

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STANDARD BEHAVIOR CHART (aka STANDARD CELERATION)

Used in sub-area of behavior analysis called Precision Teaching (PT not gym class!)

PT uses FLUENCY as important dimension of behavior

FLUENCY = high accuracy + HIGH SPEED STANDARD = everyone uses the same basic

graph (see next) CELERATION = measure of acceleration or

deceleration of behavior

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STANDARD BEHAVIOR CHART (aka STANDARD CELERATION) ACCELERATION = rate of behavior keeps

increasing as time passes Note the Y axis on each graph Left one is arithmetic scale; right one is a logarithmic

(ratio) scale

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STANDARD CELERATION CHART

Each major tick mark is 10x the rate from previous tick mark; Allows us to see how long it takes for a behavior to increase by 10 times (PT has identified certain minimal levels of fluency that predict later success in school)

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STANDARD CELERATION See this link for background information about fluen

cy training

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End of chapter 6-Cooper