# Covariance Parameters (generalized linear mixed models)

This view displays the covariance parameter estimates and related statistics for residual and random effects. These are advanced, but fundamental, results that provide information on whether the covariance structure is suitable.

**Summary table. **This is a quick reference for the number
of parameters in the residual (**R**) and random effect (**G**)
covariance matrices, the rank (number of columns) in the fixed effect
(**X**) and random effect (**Z**) design matrices, and the number
of subjects defined by the subject fields that define the data structure.

**Covariance parameter table. **For the selected effect, the
estimate, standard error, and confidence interval are displayed for
each covariance parameter. The number of parameters shown depends
upon the covariance structure for the effect and, for random effect
blocks, the number of effects in the block. If you see that the off-diagonal
parameters are not significant, you may be able to use a simpler covariance
structure.

**Effects. **If there are random effect blocks, then there
is an Effect dropdown list for selecting the residual or random effect
block to display. The residual effect is always available.

**Groups.** If a residual or random effect block has a group
specification, then there is a Group dropdown list for selecting the
group level to display.

**Multinomial. **If the multinomial distribution is in effect,
then the Multinomial drop-down list controls which target category
to display. The sort order of the values in the list is determined
by the specification on the Build Options settings.