provide me with feedback with the most appropriate dimension to measure and measurement system to use for the following behavior:

 

Target behavior: Off-Task behavior

Operational definition: Off-task behavior is defined as Pablo engaging in any other activity (searching the internet, scrolling through apps on his phone) that is unrelated to the current assigned task for more than 30 seconds.

 

I gave it a try and selected the following: 

Dimension to measure: Duration 

Measurement system: Time sampling (partial-interval recording)