Spatial scaling, proportional thinking, and numerical understanding in 5- to 7-year-old children

The present study investigated the role of spatial scaling and proportional-reasoning skills in children's number-line estimations. Proportional strategies in number-line estimations might suggest that correlations between number-line knowledge and scaling are driven by proportional thinking. However, analyses of data on spatial scaling, proportional reasoning, counting skills, and number-line knowledge from 5- to 7-year-old children (N = 65) showed significant correlations between spatial-scaling performance and number-line knowledge, even after age, counting skills, common method variance, and proportional reasoning were accounted for. Thus, spatial scaling is related to variance in number-line estimations due to mechanisms beyond proportional reasoning. The ability to mentally transform magnitudes may be the additional common underlying process.