Design
A factorial design was applied with the within-participant factors diameter (2) and water level (2).
Each combination of diameter and water level was presented three times. Thus, a total of 12 experimental
trials were presented per task. Measurement repetitions were presented in blocks. The order of
the stimuli within the blocks varied between participants and was determined by a randomizing program
with the restriction that the same levels of one factor did not appear in immediate succession