Counterbalancing task order across listeners cancels learning effects, unlike fixed-order testing.

Evidence

It is common to try a pilot test with a small number of listeners to check the test procedure and the presence of any additional independent variables. Some independent variables can be controlled by ensuring they remain constant (for example, the ventilation might be turned off, and measures could be taken to reduce background noise). Others can be controlled through the test procedure (for example, any learning effect could be explored by playing the stimuli in a different order to different subjects or asking each listener to take the test twice, with the stimulus order being reversed the second time). — David M. Howard, Jamie Angus, Acoustics and Psychoacoustics, 2383

Categorization

• XREF: Connects to general experimental-design methodology familiar from psychology and behavioral research.