This function generates the design matrix for an item

designmatrix(Kj = NULL, model = "GDINA", Qj = NULL, no.bugs = 0)

Arguments

Kj

Required except for the MS-DINA model; The number of attributes required for item j

model

the model associated with the design matrix; It can be "GDINA","DINA","DINO", "ACDM","LLM", "RRUM", "MSDINA", "BUGDINO", and "SISM". The default is "GDINA". Note that models "LLM" and "RRUM" have the same design matrix as the "ACDM".

Qj

the Q-matrix for item j; This is required for "MSDINA", and "SISM" models; The number of rows is equal to the number of strategies for "MSDINA", and the number of columns is equal to the number of attributes.

no.bugs

the number of bugs (or misconceptions). Note that bugs must be given in the last no.bugs columns.

Value

a design matrix (Mj). See de la Torre (2011) for details.

References

de la Torre, J. (2011). The generalized DINA model framework. Psychometrika, 76, 179-199.

Examples

if (FALSE) {
designmatrix(Kj = 2, model = "GDINA")
designmatrix(Kj = 3, model = "DINA")
msQj <- matrix(c(1,0,0,1,
                 1,1,0,0),nrow=2,byrow=TRUE)
designmatrix(model = "MSDINA",Qj = msQj)
}