Original Research

From whole number to real number: Applying Rasch measurement to investigate threshold concepts

Caroline Long
Pythagoras | Issue 70 | a37 | DOI: https://doi.org/10.4102/pythagoras.v0i70.37 | © 2009 Caroline Long | This work is licensed under CC Attribution 4.0
Submitted: 01 September 2009 | Published: 01 September 2009

About the author(s)

Caroline Long, The Centre for Evaluation and Assessment, University of Pretoria , South Africa

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The developments in mathematics that take place in Grades 7 to 9 constitute critical nodes in a learner’s scholing. One of the major transitions to be made is from whole numbers to real numbers, which involves theunderstanding of rational (and irrational) numbers, and concepts such as ratio, proportion and percent. I hypothesise that ratio is a threshold concept that provides the conceptual gateway to higher order concepts. The research problem is to describe the learning challenges and provide an array of insightsand strategies that will inform teaching. The theory of conceptual fields provides the framework for this research (Vergnaud, 1988). The Rasch measurement model (Rasch, 1960/1980) articulates the qualitative and quantitative aspects of the research. This paper provides an overview of the broader study and reports on an aspect of the data analysis.


Rasch model;


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Crossref Citations

1. Proportional reasoning as a threshold to numeracy at university: A framework for analysis
Pam Lloyd, Vera Frith
Pythagoras  vol: 34  issue: 2  year: 2013  
doi: 10.4102/pythagoras.v34i2.234