qbstep {qmethod}

Q Methodology: Single step for the bootstrap

Description

Bootstraping of Q methodology using PCA.

Usage

qbstep(subdata, subtarget, indet, 
       nfactors, nqsorts, nstat, 
       qmts = qmts, qmts_log = qmts_log, 
       rotation = "unknown", 
       flagged = flagged, cor.method="pearson", ...)

Arguments

subdata

resampled dataset of Q-sorts.

subtarget

target matrix, adapted to match the rows of the resampled dataset.

indet

method to solve the double indeterminacy issue when bootstrapping Principal Components Analysis (PCA). "procrustes" for procrustes rotation from MCMCpack, "qindtest" for simple solution valid for at least up to 3 factors extracted (see references), "both" for a "qindtest" and a "procrustes" rotation, or "none" for no solution. The latter is not recommended because it introduces inflated variability. If "none" is selected, each replication is rotated using the method set in rotation.

nfactors

number of factors in the study.

nqsorts

number of Q-sorts in the study.

nstat

number of statements in the study.

qmts

data frame with two rows and at least one column. This is automatically created when this function is called from qmboots(see Note below).

qmts_log

data frame with two rows and at least one column. This is automatically created when this function is called from qmboots(see Note below).

rotation

rotation method, defaults to "none".

flagged

matrix or data frame of nqsorts rows and nfactors columns, with TRUE values for the Q-sorts that are flagged. Automatic flagging can be aplied using qflag. Manual flagging can be done by providing a logical matrix with nqsorts rows and nfactors columns to the argument flagged.

cor.method

character string indicating which correlation coefficient is to be computed, to be passed on to the function cor: "pearson" (default), "kendall", or "spearman".

...

other arguments to be passed on to qzscores or to principal.

Details

This function performs a single step within a bootstrap of Q methodology data. It takes one resample, performs the Q method analysis, checks for indeterminacy issues, and corrects them if necessary by calling the function qindtest or qpcrustes.

Value

step_res

summary of the analysis.

Note

This function is called within the function qmboots. Not intended to be used separately.

Author(s)

Aiora Zabala

References

Zabala, Pascual (2016) Bootstrapping Q Methodology to Improve the Understanding of Human Perspectives. PLoS ONE 11(2): e0148087.

See Also

qmethod and qmboots in this package.