Computes the residuals for vectors of response patterns.
Usage
## S3 method for class 'gpcm'
residuals(object, resp.patterns = NULL, order = TRUE, ...)
## S3 method for class 'grm'
residuals(object, resp.patterns = NULL, order = TRUE, ...)
## S3 method for class 'ltm'
residuals(object, resp.patterns = NULL, order = TRUE, ...)
## S3 method for class 'rasch'
residuals(object, resp.patterns = NULL, order = TRUE, ...)
## S3 method for class 'tpm'
residuals(object, resp.patterns = NULL, order = TRUE, ...)
Arguments
object
an object inheriting either from class gpcm, class grm, class ltm, class rasch or class
tpm.
resp.patterns
a matrix or a data.frame of response patterns with columns denoting the
items; if NULL the expected frequencies are computed for the observed response patterns.
order
logical; if TRUE the response patterns are sorted according to the residual estimates.
...
additional arguments; currently none is used.
Details
The following residuals are computed:
(O_i - E_i) / E_i^(1/2),
where
O_i and E_i denote the observed and expected frequencies for the ith response pattern.
Value
A numeric matrix containing the observed and expected frequencies as well as the residual value for
each response pattern.