Brentari Eugenio, Golia Silvia
University of Brescia, Italy.
J Appl Meas. 2008;9(1):45-56.
In the present paper, the Rasch measurement model is used in the validation and analysis of data coming from the satisfaction section of the first national survey concerning the social services sector carried out in Italy. A comparison between two Rasch models for polytomous data, that is the Rating Scale Model and the Partial Credit Model, is discussed. Given that the two models provide similar estimates of the item difficulties and workers satisfaction, for almost all the items the response probabilities computed using the RSM and the PCM are very close and the analysis of the bootstrap confidence intervals shows that the estimates obtained applying the RSM are more stable than the ones obtained using the PCM, it can be conclude that, for the present data, the RSM is more appropriate than the PCM.