Fig. 4

Mean color-object association ratings for paper, plastic, glass, metal, compost, and trash. Colors are sorted along the x-axis from most weakly associated to most strongly associated with each object. Bar colors represent the colors that were judged (also see x-axis label and corresponding coordinates in Additional file 1: Table S1). Error bars represent the ± standard errors of the means. See Additional file 1 for details on how the data were collected