vcov.ltm {ltm} | R Documentation |
Extracts the asymptotic variance-covariance matrix of the MLEs from a ltm
object.
## S3 method for class 'ltm': vcov(object, robust = FALSE, ...)
object |
an object inheriting from class ltm . |
robust |
logical; if TRUE the sandwich estimator is used. |
... |
additional arguments; currently none is used. |
a numeric matrix representing the estimated covariance matrix of the maximum likelihood estimates.
Dimitris Rizopoulos dimitris.rizopoulos@med.kuleuven.be
m <- ltm(Lsat ~ z1) vcov(m) sqrt(diag(vcov(m))) # standard errors