Describe partial-interval recording and one potential bias associated with it.

• A. Records whether the behavior occurred for the entire interval; tends to underestimate frequency.
• B. Records whether the behavior occurred at the end of the interval; approximates occurrence rate.
• C. Records the duration of each occurrence; overestimates duration.
• D. Records whether the behavior occurred at any time during an interval; tends to overestimate frequency.

Answer: (D)

Partial-interval recording checks whether the target behavior happened at any time during each predefined interval. It doesn’t track how many times it occurred or how long it lasted, just whether it occurred at least once within the interval. The bias here arises because a brief moment of behavior inside an interval still counts as an occurrence for that entire interval. As a result, the method tends to overestimate how often the behavior is actually occurring when you convert the data into a rate or percentage of intervals with occurrences. In contrast, other methods either require the behavior to occur for the whole interval (which underestimates frequency) or check only at a single moment (which provides a rough approximation).