Figure 5: Effects of age and mathematics education on number representations in US children.
From: Universal and uniquely human factors in spontaneous number perception

Age and mathematics ability are related to perception of number but not cumulative surface area. The figure plots the beta weights from a mixed model logistic regression showing (a) the effect of age and (b) the effect of math ability (standardized score) on number and area categorization in US children (n=32). Shaded regions represent 95% confidence intervals.