What method allows an observer to measure the length of time a behavior occurs?

Duration recording is the method that enables an observer to measure the length of time a particular behavior occurs. This technique is used predominantly when the focus is on understanding how long a specific behavior persists during an observation period. It involves documenting the exact time a behavior starts and stops, allowing for a precise measurement of its duration. This is particularly useful in situations where behaviors may vary significantly in length, providing insight into the overall engagement or intensity of the behavior over time.

In contrast, frequency recording concentrates solely on the number of times a behavior occurs within a specified time frame, offering no information about how long each instance lasts. Event sampling captures specific instances of a behavior occurring, which can be effective but does not focus on the length of those occurrences. Interval recording divides the observation period into intervals and notes whether the behavior occurs or not, thus providing a more general overview rather than detailed information about duration. Therefore, duration recording is unique in its focus on the temporal aspect of behavior.