R is a powerful open source programming environment primarily known for its statistical capabilities. In this course we will cover some advanced applications of R: distributed computing using the ...

The assessment of change in patient-reported outcomes is hindered by the fact that there are different types of change. Besides 'true' change, different types of response shift, such as recalibration, ...

An extension of the graded response model of Samejima (1969) for the measurement of variability and change is presented. In this model it is assumed that an occasion-specific latent variable is ...