| simul.rasch {pwrRasch} | R Documentation |
Simulate data according to the Rasch model
Description
This function simulates data according to the Rasch model based on user-specified item and person parameters.
Usage
simul.rasch(persons, items, sum0 = TRUE)
Arguments
persons |
Either a vector of specified person parameters or an integer indicating the number of persons. |
items |
Either a vector of specified item parameters or an integer indicating the number of items. |
sum0 |
If |
Details
If persons is an integer value, the corresponding parameter vector
is drawn from N(0, 1.5). If items is an integer value, the corresponding parameter vector
is equally spaced between [-3, 3]. Note that item parameters need to be normalized to sum-0.
This precondition can be overruled using argument sum0 = FALSE.
Value
Returns a 0-1 matrix according to the Rasch model.
Author(s)
Takuya Yanagida takuya.yanagida@univie.ac.at, Jan Steinfeld jan.steinfeld@univie.ac.at
References
Kubinger, K. D., Rasch, D., & Yanagida, T. (2009). On designing data-sampling for Rasch model calibrating an achievement test. Psychology Science Quarterly, 51, 370-384.
Kubinger, K. D., Rasch, D., & Yanagida, T. (2011). A new approach for testing the Rasch model. Educational Research and Evaluation, 17, 321-333.
See Also
Examples
## Not run:
# simulate Rasch model based data
# 100 persons, 20 items,
# person parameter drawn from a normal distribution: N(0,1.5)
# item parameters equally spaced between [-3, 3]
simul.rasch(100, items = 20)
# simulate Rasch model based data
# 100 persons, 17 items
# person parameter drawn from a uniform distribution: U[-4, 4]
# item parameters: [-4.0, -3.5, -3.0, ... , 3.0, 3.5, 4.0]
simul.rasch(runif(100, -4, 4), items = seq(-4, 4, by = 0.5))
## End(Not run)