Bar graph
A bar graph uses vertical or horizontal bars to compare values across separate categories or to summarize data, such as means for each condition.
In a bar graph, each bar's height (or length) represents a single value for a category, and the bars are not connected. Common uses include comparing the mean rate of behavior in baseline and intervention, showing the percentage of correct responses for different targets, or showing how often behavior occurred in different activities or times of day.
Bar graphs are good for simple, clear summaries, especially when sharing results with caregivers or teachers. Some functional analysis and preference assessment results are also shown this way, for example the percentage of trials each item was chosen.
Because a bar usually summarizes many sessions into one value, a bar graph can hide important features of the data. It does not show trend or variability within a condition, and a single mean can make an unstable or worsening pattern look acceptable. For day-to-day progress monitoring the team relies on line graphs, and bar graphs are used to supplement them.
Example and non-example
| Example | After a paired stimulus preference assessment, an RBT helps prepare a graph with one bar for each of six toys showing the percentage of trials each toy was selected. |
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| Non-example | A graph that plots a client's daily percentage correct as points joined by a line across 20 sessions is a line graph. |
Don't confuse it with
| Line graph | A bar graph compares categories or summaries with separate bars; a line graph shows session-by-session change over time with connected points. |
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| Scatterplot | A bar graph summarizes values by category; a scatterplot records whether behavior occurred in each time block across days to show patterns. |
Test yourself
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Question 1A supervisor wants to show caregivers the average number of tantrums per session in baseline and the average in intervention, as two values side by side. Which display fits this purpose?
Show answer
A: A bar graph. Bar graphs are suited to comparing summary values, such as averages, across separate categories or conditions.
- B: A cumulative record shows a running total of responses over time, not two averages side by side.
- C: A scatterplot shows when behavior occurs across times of day and days, not a comparison of two averages.
- D: A session-by-session line graph shows change over time; the supervisor wants just two summary values compared.
Task A.4 · 40-hour curriculum section C
Answer every question to see your score.
On the RBT exam
This term belongs to task A.4 Entering data and updating graphs in content area A, Data Collection and Graphing, which is 13 of the 75 scored questions.