IPCA: IPCA

In SICSresearch/IRTpp_old: Estimating IRT parameters using the IRT Methodology

Description

Iterative Principal Components Analysis (IPCA) Computes the Iterative components analysis to find dimensionality of a huge data matrix with entries 0 and 1.

Usage

IPCA(data, h7 = 0.9, h2 = 0.2, hn = 10, angu = 15, clas = TRUE,
  reclas = TRUE)

Arguments

test:	Dichotomic matrix data.
h7:	Threshold to define the items not classificated
h2:	Threshold to define the unidimensionality
hn:	number of items in each cluster
angu:	Threshol to define the angle of each cluster (it could change)
clas:	If is TRUE then the classification is made, default is TRUE
reclas:	If is TRUE then the reclassification is made, default is TRUE If clas=TRUE and reclas=TRUE then the results are:

Value

n.submatrix: Total of submatrices Before and After reclassification

n.ipm.befrec: Number of items per matrix before reclassification. If clas=TRUE and reclas=FALSE or clas=FALSE and reclas=FALSE, then this result is NULL.

n.ipm.aftrec: Number of items per matrix after reclassification. If clas=TRUE and reclas=FALSE or clas=FALSE and reclas=FALSE, then this result is NULL.

n.ipm.clas: Number of items per matrix after classification. If clas=FALSE and reclas=TRUE or clas=FALSE and reclas=FALSE, then this result is NULL.

p.axes: Principal Axis of each submatrix

ipm: Matrix of items on each submatrix before classification. If clas=FALSE and reclas=TRUE or clas=FALSE and reclas=FALSE, then this result only show the first classification.

ipmc: Matrix of items on each submatrix after classification. If clas=FALSE and reclas=TRUE or clas=FALSE and reclas=FALSE, then this result is NULL.

DPM: Data of each submatrix (List object)

inc: Items not classified in a principle

Author(s)

SICS Research Group, Universidad Nacional de Colombia [e-mail]

References

Montenegro, A.M. & Ordo\~nez, M.F & P\'aez, S (2015) A Novel Methodology Based on Item Responde Theory to Find Dimensionality and Emergent Information from Textual Data. Journal of Infometrix(Submited)

See Also

z3_itemf, x2_itemf

Examples

irtpp()

SICSresearch/IRTpp_old documentation built on May 9, 2019, 11:12 a.m.