MLD children switch between direct subtraction and subtraction by addition only when the numerical distance between subtrahend and difference is large¶

Claim · All claims
Evidence · 1 study (2 entries) · causal r2 · q3
Currency · newest study 2014 · not yet checked against its sources · not reviewed by a person

Subclaims¶

q3 i? The magnitude × format × distance interaction was significant, F(1, 172) = 50.64, p < .01, with the magnitude × format interaction significant only for large-distance problems. → Peters 2014 q3 i? Large-distance S > D problems were solved faster in the addition format, t(172) = 6.29, p < .01, whereas large-distance S < D problems were solved faster in the subtraction format, t(172) = -6.52, p < .01. → Peters 2014 (2)

Evidence¶

Peters 2014¶

Peters, G., De Smedt, B., Torbeyns, J., Verschaffel, L., & Ghesquière, P. (2014). Subtraction by addition in children with mathematical learning disabilities. Learning and Instruction, 30, 1-8. https://doi.org/10.1016/j.learninstruc.2013.11.001

q3 · i? · causal · r2

2 × 2 × 2 repeated measures ANOVA on reaction times of 44 children with MLD across four problem types and two presentation formats. The three-way interaction was significant; no effect size was printed.

"Most importantly, the magnitude × format × distance interaction was significant, F(1, 172) = 50.64, p < .01 (see Figure 2)."

Peters 2014 (2)¶

Peters, G., De Smedt, B., Torbeyns, J., Verschaffel, L., & Ghesquière, P. (2014). Subtraction by addition in children with mathematical learning disabilities. Learning and Instruction, 30, 1-8. https://doi.org/10.1016/j.learninstruc.2013.11.001

q3 · i? · causal · r2

Tukey-Kramer adjusted post-hoc comparisons from the same ANOVA. Format effects ran in opposite directions for the two large-distance problem types; no effect size was printed.

"The large-distance S > D problems in the addition format (e.g., 79 + . = 83) were solved faster than the same problems in the subtraction format (e.g., 83 − 79 = .), t(172) = 6.29, p < .01, whereas the large-distance S < D problems were solved faster in the subtraction (e.g., 83 − 4 = .) than in the addition format (e.g., 4 + . = 83), t(172) = -6.52, p < .01."

Discussion¶

Related Claims¶

• At the individual level, the Switch-Model most frequently provided the best fit to MLD children's reaction times, though a substantial subgroup fit the DS-Model or no model — related
• Children with MLD switch between direct subtraction and subtraction by addition based on the magnitude of the subtrahend when solving two-digit subtractions — related
• Reaction times showed significant main effects of presentation format and numerical distance, but no main effect of magnitude — related
• MLD children's accuracy was low overall and varied by problem type and presentation format — related
• Symbolic numerical magnitude comparison has a more unique association than number line estimation with children's speed on indirect-addition subtraction items — related
• The association between numerical magnitude processing and subtraction is more prominent for items eliciting indirect addition than for direct subtraction items — related