irtoys (version 0.1.4)

grp: Bin the latent variable estimates

Description

Groups a vector of estimates of the latent variable into a histogram-like object. Typically invoked by function itf, unless the user wishes to access some of the non-default settings.

Usage

grp(theta, bins=9, breaks=NULL, equal="count", type="meds")

Arguments

theta

The latent variable estimates to be binned

bins

Desired number of bins

breaks

A vector of cutpoints. Overrides bins if present.

equal

Either "width" for bins of equal width, or "count" for bins with roughly counts of observations. Default is "quant"

type

The points at which itf will evaluate the IRF. One of "mids" (the mid-point of each bin), "meds" (the median of the values in the bin), or "means" (the mean of the values in the bin). Default is "m

Value

• A list of:
• breaks
  The breaks between adjacent bins
• counts
  The number of values in each bin
• ref
  Depending on ref.type, the mids of the bin, or the mean or median of the values in the bin

See Also

itf

Examples

data(Scored)
p.2pl  <- est(Scored, model="2PL", engine="ltm")
th.mle <- mlebme(resp=Scored, ip=p.2pl)
gr     <- grp(th.mle, bins=7)