If observers are more tired and less astute when making posttest observations than when making pretest observations, what threat is operating?

Question

Quizplus · Accepted Answer

Instrumentation threats occur when there is a change in the measurement instrument or observers over time. In this case, the observers' increased tiredness and decreased astuteness between pretest and posttest observations represent a change in the observers' condition, which can affect the consistency and reliability of the observations.

If Observers Are More Tired and Less Astute When Making