Measuring Time-Based Behaviors
Not all behaviors are counts. Sometimes, time is the critical dimension. Confusing these three is a common exam error.
Duration (How Long?)
The total time a behavior occurs from start to finish. Use this for tantrums or play episodes. "Johnny cried for 20 minutes." Endurance.
Latency (How Soon?)
The time between the SD (instruction) and the start of the response. "I said 'Sit down,' and it took him 10 seconds to start sitting." Use this for non-compliance or slow processing. Reaction time.
Inter-Response Time (IRT) (Time Between)
The time between the end of one response and the start of the next. The gap between behaviors. "He took a bite of food every 30 seconds." Use this to slow down fast eaters or speed up slow workers. Pacing.