C.10: Graph data to communicate relevant quantitative relations (e.g., equal-interval graphs, bar graphs, cumulative records).
Free practice questions for this part of the BCBA, with an explanation for every option.
A BCBA plots a client's completed self-care steps on a cumulative record. From the session 8 data point to the session 11 data point, the data path is flat (horizontal). What does this mean?
- A. The client kept responding at a steady, moderate rate.Incorrect. On a cumulative record, steady responding produces a rising line with constant slope, not a flat one.
- B. The client's rate of responding was at its highest.Incorrect. The highest rate would show as the steepest slope.
- C. The data were lost and should be treated as missing.Incorrect. A flat segment shows zero responding. Missing data would show as a break in the data path.
- D. No responses occurred in sessions 9, 10, and 11.Correct. Each point on a cumulative record adds the new responses to the previous total. If the total does not change from session 8 to session 11, sessions 9–11 had zero responses.
A BCBA wants to show a parent the average number of problem behaviors per session for each of four types of activity (meals, bath, homework, play) in one simple summary display. Which graph is most appropriate?
- A. A Standard Celeration ChartIncorrect. The Standard Celeration Chart shows proportional change in rate over time, which is more complex than this purpose requires.
- B. A line graph with sessions on the x-axisIncorrect. A session-by-session line graph shows change over time, not a simple comparison of averages across activity types.
- C. A cumulative recordIncorrect. Cumulative records show responding accumulating over time, not summary comparisons between categories.
- D. A bar graphCorrect. Bar graphs work well for comparing summary values (such as means) across discrete categories that are not on a time continuum.
A supervisee's line graph shows baseline and intervention for one client's self-injury. The supervisee drew one continuous data path linking the last baseline point to the first intervention point and left out the condition labels. Which correction best follows standard graphing conventions?
- A. Keep the connected data path, because it shows the immediacy of change.Incorrect. Connecting points across conditions implies continuity between different conditions and can mislead readers. Immediacy is judged from the points next to the phase line.
- B. Add a vertical phase change line, break the data path across it, and label each condition.Correct. Condition changes are marked with vertical lines, data paths are not connected across them, and each phase gets a clear label.
- C. Convert the graph to a bar graph showing the mean of each phase.Incorrect. Means hide trend, variability, and immediacy, which are needed for visual analysis.
- D. Change the y-axis to a logarithmic scale so the change looks clearer.Incorrect. Changing the scale does not fix the missing phase markers and could change how readers perceive the data.