Unidimensionality in the Rasch model: how to detect and interpret

Authors

  • Eugenio Brentani Università degli Studi di Brescia
  • Silvia Golia Università degli Studi di Brescia

DOI:

https://doi.org/10.6092/issn.1973-2201/3508

Abstract

Unidimensionality, that is the items in a questionnaire measure only a single construct, is a fundamental requirement for the Rasch model. The paper deals with the detection of unidimensionality making use of principal components analysis of residuals and item fit statistics. Simulated bi-dimensional data sets are analized in order to find regolarities in the behavoiur of these statistical tools. The results are applied to a real database coming from the satisfaction section of the first national survey concerning the social services sector carried out in Italy

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Published

2007-09-30

How to Cite

Brentani, E., & Golia, S. (2007). Unidimensionality in the Rasch model: how to detect and interpret. Statistica, 67(3), 253–261. https://doi.org/10.6092/issn.1973-2201/3508

Issue

Vol. 67 No. 3 (2007)

Section

Articles

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Copyright (c) 2007 Statistica

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