Partial correlations between measures of ANS acuity and exact calculation, controlling for age, intelligence and spelling.

TA = typically achieving; MD = mathematical difficulties; w: internal Weber fraction; cv: coefficient of variation. *Correlation is significant at the 0.05 level; **Correlation is significant at the 0.01 level.Partial correlations between measures of ANS acuity and exact calculation, controlling for age, intelligence and spelling.TA为典型成就群体（typically achieving, TA），MD为数学困难群体（mathematical difficulties, MD）；w为内部韦伯分数（internal Weber fraction, w），cv为变异系数（coefficient of variation, cv）。*表示相关在0.05水平上具有统计学显著性；**表示相关在0.01水平上具有统计学显著性。控制年龄、智力与拼写能力后，近似数字系统敏锐度（Approximate Number System acuity, ANS）各项测量指标与精确计算能力测量指标间的偏相关系数。