A niche perceptual check — whether products shown packed together in an ad appear to have any visible gap between them, across three items.
7-point Likert (1=strongly disagree, 7=strongly agree)
Zhang, Y., Kwak, H., Puzakova, M., & Taylor, C.R. (2021). Space Between Products on Display: The Impact of Interspace on Consumer Estimation of Product Size. Journal of the Academy of Marketing Science, 49(6), 1109–1131.
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