A standardised set of images for judgements of proportion

In the present work, we present normative data for a set of 39 original clipart-style images that can be used as material in studies involving judgements of proportion. The original images are drawings that depict different day-to-day scenarios (e.g., lighted windows in a building; books on a shelf) and each has seven variants of different proportions (from 20% to 80%) belonging to different categories (discrete vs continuous; social vs non-social; natural vs artificial; stimuli physical dimensions; number of referents). Normative data for these images are presented in an interactive database (available at https://judgment-images-and-norms.shinyapps.io/estimates_interactive/ ), corresponding to the means of proportion estimates (in percentage form), the perceived ease of making such estimates, the perceived level of familiarity and liking for each image, and the relationships between these variables. In the paper, we analyse the data at an individual level, addressing how the latter judgements are related to the proportion estimates, how those estimates are related to objective proportions, and how these relationships are moderated by image category. The analyses presented in this paper aim to aid readers in selecting images that enable them to better address specific influences on proportional estimates or to control for those influences in their studies.