Rachel, a strong-willed, wealthy, Jewish department-store owner is used by the writers to easily expose Sterling Cooper's misogyny and latent (nearly blatant) difficulty with dealing with a Jewish client.
Indeed, in the present study, data were simulated by adjusting the difficulty of the items on the mean value of the latent trait (the mean difficulty parameters was equal to the mean of the simulated latent trait).
The Rasch person-item map displays the person parameter distribution on the latent dimension and the item difficulties.
This model can independently assess the item difficulty parameters and latent trait level of a sample of individuals in the same linear continuum.
Chemoprophylaxis of contacts of infectious tuberculosis (TB) cases is recommended for TB control, particularly in endemic countries, but is hampered by the difficulty to diagnose latent TB infection (LTBI), classically assessed through response to the Tuberculin Skin Test (TST).
Another major source of difficulty is missing (latent) variables.
The test instrument is always constructed to measure ability and difficulty on the latent construct, not on the individual items.
The two parameter model estimates the examinees performance or ability on a latent trait with varying item difficulty and discrimination using dichotomous responses.
The Rasch person-item map shows the person parameter distribution on the latent underlying dimension and the item difficulties (Fig. 1).
The ordering of the items based on their locations on the latent dimension (i.e., their difficulty; see also Table 2) is in line with the ordering based on the estimation of the items' difficulties by our expert group in the test development process.
The difficulty parameters define the latent variable of conceptual competencies on a scale from −1.506 to.748 logits and the latent variable of statistical competencies on a scale from −1.809 to.663 logits.
