simMPRM: simulate data according to MPRM
In pcIRT: IRT Models for Polytomous and Continuous Item Responses

Description Usage Arguments Details Value Author(s) References See Also Examples

With this function data sets according to the multidimensional polytomous Rasch model (MPRM) are simulated

1	simMPRM(itempar, persons = 500, seed = NULL)

`itempar`	a matrix with item category parameters; each row represents a category and each column an item (see details)
`persons`	an integer representing the number of persons (observations) of the data set (see details)
`seed`	a seed for the random number generated can optionally be set

Data are generated with category values starting with 0. Thus the first row of the matrix containing the item parameters is matched to the category value 0 and so on. The last category is the reference category. Please note, that the item category parameters of the last category have to be 0 (due to parameter normalization)!

Person parameters are generated by a standard normal distribution.

`datmat`	simulated data set
`true_itempar`	the fixed item parameters according to the input
`true_perspar`	the fixed person parameters

Christine Hohensinn

Fischer, G. H. (1974). Einfuehrung in die Theorie psychologischer Tests [Introduction to test theory]. Bern: Huber.

Rasch, G. (1961). On general laws and the meaning of measurement in psychology, Proceedings Fourth Berekely Symposium on Mathematical Statistiscs and Probability 5, 321-333.

simCRSM

#set item parameters
item_p <- rbind(matrix(c(-1.5,0.5,0.5,1,0.8,-0.3, 0.2,-1.2), ncol=4),0)

#number of persons
pn <- 500

#simulate data set
simdatM <- simMPRM(item_p, pn)