Attitudes towards Roma people and migrants: a comparison through a Bayesian multidimensional IRT model

In the context of social psychological research on relations between cultural defined groups, the main topics of interest include ethnic prejudice, attitudes and stereotypes. In the present study, in order to measure and compare attitudes towards Roma people and migrants and to investigate how these attitudes vary according to individual characteristics, we develop an integrated model which embeds a multidimensional Item Response Theory model for polytomous data into a structural equation formulation. Item and person parameters and structural coefficients are estimated on data collected through a web survey. Full probabilistic inference is performed by applying Markov chain Monte Carlo techniques