BDS Modules C.00-C.08 Measurement and Data
Analysis: Expert Certification Assessment
This comprehensive assessment covers core principles in measurement, data display, and
interpretation, aligning with the foundational standards established in BDS Modules C.00
through C.08, which correspond to the Measurement section of the Behavior Analyst
Certification Board (BACB) task list. The following 65 questions are designed to test the
technical and conceptual mastery required for expert clinical practice.
I. Foundational Concepts and Operational Definitions (C.00, C.01,
C.11) (Q1-Q10)
Q1
A clinical supervisor reviewing a trainee’s data notices that while the rate of client aggression is
clearly decreasing (a favorable general direction), the data points are widely scattered and do
not cluster closely around the mean path. What term best describes the extent to which these
data points deviate from one another? A. Level B. Trend C. Slope D. Variability
Correct Answer: D. Variability
Detailed Rationale: The overall direction of the data path is described as the Trend. The
overall value around which the data measures converge on the y-axis is the Level. Variability
refers specifically to the degree of scatter or "bounce" among the data points. High variability,
even alongside a favorable trend, indicates instability and suggests a lack of experimental
control or the presence of uncontrolled extraneous variables. This instability compels the analyst
to pause intervention and conduct further assessment before the trend can be reliably trusted.
Q2
Which scenario most accurately reflects the fundamental property of Level in visual data
analysis? A. The data path is steadily increasing across baseline sessions. B. The median
frequency of elopement is 14 times per week during the intervention phase. C. The behavior
count changes significantly between Tuesday and Wednesday. D. The logarithmic ratio of
improvement exceeds 2X.
Correct Answer: B. The median frequency of elopement is 14 times per week during the
intervention phase.
Detailed Rationale: The Level is defined as the value on the vertical (y) axis around which a
series of data measures converge. It represents the average or central tendency of the data
points within a condition. Option A describes the Trend. Option C describes daily fluctuations
(Variability). Option D relates to Celeration (proportional rate of change). Reporting the median
or mean value provides the most accurate reflection of the level.
Q3
When establishing an operational definition for a client's "toy throwing" behavior, the behavior
analyst defines it as: "Any instance in which the client forcefully projects a toy object (excluding
,soft foam objects) into the air such that the object travels more than three feet from the client,
measured from the moment the object leaves the hand until the object lands." This definition
meets the criteria of being objective, clear, and complete because it specifies: A. The assumed
function (automatic reinforcement) and the necessary magnitude. B. The social significance and
reliability measures. C. The topography, a measurable dimension (three feet), and a clean onset
and offset. D. The internal emotional state of the client and the functional response class.
Correct Answer: C. The topography, a measurable dimension (three feet), and a clean
onset and offset.
Detailed Rationale: A high-quality operational definition must be Objective (observable
behavior, not inferred states), Clear (easily understood by others), and Complete (specifying
boundaries, onset, and offset). The provided definition describes the physical form
(topography), includes quantifiable requirements (distance, excluded objects), and explicitly
includes a clear onset (object leaves hand) and offset (object lands). Without a clear onset and
offset, two observers measuring duration or latency would likely record different start/stop times,
fundamentally compromising the accuracy and reliability of the data.
Q4
A novice practitioner attempts to operationally define "frustration" as "when the client appears
upset or withdrawn for periods longer than two minutes." Which essential characteristic of a
strong operational definition is violated, and why? A. Clarity, because "two minutes" is too
specific. B. Completeness, because non-examples were not provided. C. Objectivity, because
"appears upset" and "withdrawn" are subjective, inferred states. D. Trend, because it describes
a temporal dimension rather than occurrence.
Correct Answer: C. Objectivity, because "appears upset" and "withdrawn" are subjective,
inferred states.
Detailed Rationale: A definition must be objective to ensure that data collectors measure the
observable parts of the behavior or environment, rather than subjective internal states like
"upset" or "withdrawn". Objectivity requires that inferred descriptions be translated into
quantifiable actions (e.g., instead of "upset," measure "crying for 30 seconds," or "pounding a
fist on the desk"). The ability of multiple people to take the same data (reliability) is directly
contingent upon the objectivity of the definition.
Q5
An analyst wishes to track the effectiveness of a new social skills program aimed at reducing a
client's tendency to interrupt conversations. Which operational definition is the most
professional, objective, and complete? A. Speaking out of turn when others are talking in a rude
way. B. Interrupting peers, which is defined as initiating a vocal utterance greater than 1 second
in duration while a peer is already speaking. Excludes instances where the client is replying
directly to a question posed to them. C. Verbal aggression, scored only if the client appears
angry. D. Any vocalization that occurs after a social cue is presented.
Correct Answer: B. Interrupting peers, which is defined as initiating a vocal utterance
greater than 1 second in duration while a peer is already speaking. Excludes instances
where the client is replying directly to a question posed to them.
Detailed Rationale: Option B fulfills the criteria of being objective, clear, and complete (OCC). It
identifies the specific topography and duration boundary ("vocal utterance greater than 1
second"), provides a clear context for occurrence ("while a peer is already speaking"), and
, includes a non-example ("excludes instances where the client is replying directly") to specify
boundaries and reduce ambiguity.
Q6
Which element is NOT considered one of the three fundamental properties of measurable
behavior change displayed on a graph? A. Trend B. Level C. Variability D. Topography
Correct Answer: D. Topography
Detailed Rationale: The fundamental properties used for the visual analysis of behavior
change (C.11) are Level (the mean value), Trend (the direction of the data path), and
Variability (the degree of scatter). Topography is a measure of the physical form of the
behavior itself , typically defined in the operational definition (C.01), but it is not a property used
to analyze change over time on a standard line graph.
Q7
A behavior analyst graphs the frequency of a new skill acquisition target. The data path shows a
high, steady upward Trend but also extremely high Variability (wide scatter). What does this
pattern primarily suggest regarding the intervention? A. The intervention is highly effective and
should be continued. B. The data collection system is invalid and should be immediately
replaced. C. The intervention is partially effective, but high variability suggests the current
procedures lack sufficient experimental control. D. The baseline was too short, and the
intervention should be re-started.
Correct Answer: C. The intervention is partially effective, but high variability suggests the
current procedures lack sufficient experimental control.
Detailed Rationale: Visual analysis necessitates evaluating both the trend and the variability. A
favorable trend suggests the intervention is moving in the desired direction. However, high
variability indicates environmental instability or that important variables (confounding or
reinforcing) are intermittently affecting the behavior and are not being systematically controlled.
This instability regarding experimental control necessitates further assessment or refinement of
the procedures before the trend can be fully trusted.
Q8
A practitioner notes that a client's performance data often shows zero occurrences of the target
behavior on Mondays, 20 occurrences on Tuesdays, and 0 on Wednesdays. This rapid,
unpredictable fluctuation in occurrence between sessions would be visually analyzed as high: A.
Level shift B. Celeration C. Variability D. Duration
Correct Answer: C. Variability
Detailed Rationale: Variability is the degree to which data points are spread out or "bouncing"
away from the central tendency of the data set. The pattern (0, 20, 0) represents extreme
scatter, which is a clear indicator of high data variability, often signaling inconsistent application
of procedures or strong, uncontrolled environmental factors influencing performance.
Q9
In an ABA line graph, what information is conventionally represented on the X-axis (horizontal
axis)? A. The level of behavior. B. The quantifiable value of the dependent variable. C. The
Analysis: Expert Certification Assessment
This comprehensive assessment covers core principles in measurement, data display, and
interpretation, aligning with the foundational standards established in BDS Modules C.00
through C.08, which correspond to the Measurement section of the Behavior Analyst
Certification Board (BACB) task list. The following 65 questions are designed to test the
technical and conceptual mastery required for expert clinical practice.
I. Foundational Concepts and Operational Definitions (C.00, C.01,
C.11) (Q1-Q10)
Q1
A clinical supervisor reviewing a trainee’s data notices that while the rate of client aggression is
clearly decreasing (a favorable general direction), the data points are widely scattered and do
not cluster closely around the mean path. What term best describes the extent to which these
data points deviate from one another? A. Level B. Trend C. Slope D. Variability
Correct Answer: D. Variability
Detailed Rationale: The overall direction of the data path is described as the Trend. The
overall value around which the data measures converge on the y-axis is the Level. Variability
refers specifically to the degree of scatter or "bounce" among the data points. High variability,
even alongside a favorable trend, indicates instability and suggests a lack of experimental
control or the presence of uncontrolled extraneous variables. This instability compels the analyst
to pause intervention and conduct further assessment before the trend can be reliably trusted.
Q2
Which scenario most accurately reflects the fundamental property of Level in visual data
analysis? A. The data path is steadily increasing across baseline sessions. B. The median
frequency of elopement is 14 times per week during the intervention phase. C. The behavior
count changes significantly between Tuesday and Wednesday. D. The logarithmic ratio of
improvement exceeds 2X.
Correct Answer: B. The median frequency of elopement is 14 times per week during the
intervention phase.
Detailed Rationale: The Level is defined as the value on the vertical (y) axis around which a
series of data measures converge. It represents the average or central tendency of the data
points within a condition. Option A describes the Trend. Option C describes daily fluctuations
(Variability). Option D relates to Celeration (proportional rate of change). Reporting the median
or mean value provides the most accurate reflection of the level.
Q3
When establishing an operational definition for a client's "toy throwing" behavior, the behavior
analyst defines it as: "Any instance in which the client forcefully projects a toy object (excluding
,soft foam objects) into the air such that the object travels more than three feet from the client,
measured from the moment the object leaves the hand until the object lands." This definition
meets the criteria of being objective, clear, and complete because it specifies: A. The assumed
function (automatic reinforcement) and the necessary magnitude. B. The social significance and
reliability measures. C. The topography, a measurable dimension (three feet), and a clean onset
and offset. D. The internal emotional state of the client and the functional response class.
Correct Answer: C. The topography, a measurable dimension (three feet), and a clean
onset and offset.
Detailed Rationale: A high-quality operational definition must be Objective (observable
behavior, not inferred states), Clear (easily understood by others), and Complete (specifying
boundaries, onset, and offset). The provided definition describes the physical form
(topography), includes quantifiable requirements (distance, excluded objects), and explicitly
includes a clear onset (object leaves hand) and offset (object lands). Without a clear onset and
offset, two observers measuring duration or latency would likely record different start/stop times,
fundamentally compromising the accuracy and reliability of the data.
Q4
A novice practitioner attempts to operationally define "frustration" as "when the client appears
upset or withdrawn for periods longer than two minutes." Which essential characteristic of a
strong operational definition is violated, and why? A. Clarity, because "two minutes" is too
specific. B. Completeness, because non-examples were not provided. C. Objectivity, because
"appears upset" and "withdrawn" are subjective, inferred states. D. Trend, because it describes
a temporal dimension rather than occurrence.
Correct Answer: C. Objectivity, because "appears upset" and "withdrawn" are subjective,
inferred states.
Detailed Rationale: A definition must be objective to ensure that data collectors measure the
observable parts of the behavior or environment, rather than subjective internal states like
"upset" or "withdrawn". Objectivity requires that inferred descriptions be translated into
quantifiable actions (e.g., instead of "upset," measure "crying for 30 seconds," or "pounding a
fist on the desk"). The ability of multiple people to take the same data (reliability) is directly
contingent upon the objectivity of the definition.
Q5
An analyst wishes to track the effectiveness of a new social skills program aimed at reducing a
client's tendency to interrupt conversations. Which operational definition is the most
professional, objective, and complete? A. Speaking out of turn when others are talking in a rude
way. B. Interrupting peers, which is defined as initiating a vocal utterance greater than 1 second
in duration while a peer is already speaking. Excludes instances where the client is replying
directly to a question posed to them. C. Verbal aggression, scored only if the client appears
angry. D. Any vocalization that occurs after a social cue is presented.
Correct Answer: B. Interrupting peers, which is defined as initiating a vocal utterance
greater than 1 second in duration while a peer is already speaking. Excludes instances
where the client is replying directly to a question posed to them.
Detailed Rationale: Option B fulfills the criteria of being objective, clear, and complete (OCC). It
identifies the specific topography and duration boundary ("vocal utterance greater than 1
second"), provides a clear context for occurrence ("while a peer is already speaking"), and
, includes a non-example ("excludes instances where the client is replying directly") to specify
boundaries and reduce ambiguity.
Q6
Which element is NOT considered one of the three fundamental properties of measurable
behavior change displayed on a graph? A. Trend B. Level C. Variability D. Topography
Correct Answer: D. Topography
Detailed Rationale: The fundamental properties used for the visual analysis of behavior
change (C.11) are Level (the mean value), Trend (the direction of the data path), and
Variability (the degree of scatter). Topography is a measure of the physical form of the
behavior itself , typically defined in the operational definition (C.01), but it is not a property used
to analyze change over time on a standard line graph.
Q7
A behavior analyst graphs the frequency of a new skill acquisition target. The data path shows a
high, steady upward Trend but also extremely high Variability (wide scatter). What does this
pattern primarily suggest regarding the intervention? A. The intervention is highly effective and
should be continued. B. The data collection system is invalid and should be immediately
replaced. C. The intervention is partially effective, but high variability suggests the current
procedures lack sufficient experimental control. D. The baseline was too short, and the
intervention should be re-started.
Correct Answer: C. The intervention is partially effective, but high variability suggests the
current procedures lack sufficient experimental control.
Detailed Rationale: Visual analysis necessitates evaluating both the trend and the variability. A
favorable trend suggests the intervention is moving in the desired direction. However, high
variability indicates environmental instability or that important variables (confounding or
reinforcing) are intermittently affecting the behavior and are not being systematically controlled.
This instability regarding experimental control necessitates further assessment or refinement of
the procedures before the trend can be fully trusted.
Q8
A practitioner notes that a client's performance data often shows zero occurrences of the target
behavior on Mondays, 20 occurrences on Tuesdays, and 0 on Wednesdays. This rapid,
unpredictable fluctuation in occurrence between sessions would be visually analyzed as high: A.
Level shift B. Celeration C. Variability D. Duration
Correct Answer: C. Variability
Detailed Rationale: Variability is the degree to which data points are spread out or "bouncing"
away from the central tendency of the data set. The pattern (0, 20, 0) represents extreme
scatter, which is a clear indicator of high data variability, often signaling inconsistent application
of procedures or strong, uncontrolled environmental factors influencing performance.
Q9
In an ABA line graph, what information is conventionally represented on the X-axis (horizontal
axis)? A. The level of behavior. B. The quantifiable value of the dependent variable. C. The
