Optimizing the 0-100 Number Line Estimation Task: Scale Reduction and Its Implications for Elementary Mathematical Cognition

Authors

  • Kamal Chawla
    College of Education and Human Development, University of Maine, Orono, ME, USA
  • Julie L. Booth
    College of Liberal Arts, Temple University, Philadelphia, PA, USA
  • Christina Areizaga Barbieri
    College of Education and Human Development, University of Delaware, Newark, DE, USA

Abstract

We investigate the optimal number of items for the 0-100 number line estimation task used in research on children’s mathematical cognition and learning. In this paper, we reanalyzed data involving N = 234 students, applying an Item Response Theory- Graded Response Model to identify items with high discrimination parameters (> 1.0), iteratively reducing the 23-item scale by including items with discrimination values close to 1.0 until the reduced scale produced comparable scores to the original. Our analysis identified a reduced scale of 15 items that maintained strong correlations with–and produced consistent patterns of developmental change and predictive capability compared to–the original scale. Our findings demonstrate that a reduced 0-100 number line estimation task can effectively measure numerical magnitude understanding (accuracy and linearity of estimates) from kindergarten through third grade while saving time and resources.