- fits generalized linear mixed models by likelihood-based techniques
- conditional on normally distributed random effects, the data can have any
distribution in the exponential family
- provides the following built-in link functions:
- cumulative complementary log-log
- cumulative logit
- cumulative log-log
- cumulative probit
- complementary log-log
- generalized logit
- identity
- log
- logit
- log-log
- probit
- power with exponent λ = number
- power with exponent -2
- reciprocal
- provides the following built-in distributions and associated variance functions:
- beta
- binary
- binomial
- exponential
- gamma
- normal
- geometric
- inverse gaussian
- lognormal
- negative binomial
- Poisson
- t
- use SAS programming statements within the procedure to compute model effects,
weights, frequency, subject, group, and other variables, and to define mean
and variance functions
- fits covariance structures including:
- ANTE(1)
- AR(1)
- ARH(1)
- ARMA(1,1)
- Cholesky
- compound symmetry
- heterogeneous compound symmetry
- factor analytic
- Huynh-Feldt
- general linear
- P-spline
- radial smoother
- simple
- exponential spatial
- gaussian
- Matern
- power
- anisitropic power
- spherical
- Toeplitz
- unstructured
- permits subject and group effects that enable blocking and heterogeneity, respectively
- choice of linearization approach or integral approximation by quadrature or Laplace method
for mixed models with nonlinear random effects or nonnormal distribution
- choice of linearization about expected values or expansion about current solutions of best
linear unbiased predictors (BLUP)
- flexible covariance structures for random and residual random effects, including variance
components, unstructured, autoregressive, and spatial structures
- produce hypothesis tests and estimable linear combinations of effects
- provides a mechanism to obtain inferences for the covariance parameters.
Significance tests are based on the ratio of (residual) likelihoods or pseudo-likelihoods.
Confidence limits and bounds are computed as Wald or likelihood ratio limits.
- construct special collections of columns for the design matrices in your model.
These special collections, which are referred to as constructed effects
can include the following:
- COLLECTION is a collection effect defining one or more variables as a single effect
with multiple degrees of freedom. The variables in a collection are
considered as a unit for estimation and inference.
- MULTIMEMBER | MM is a multimember classification effect whose levels are determined
by one or more variables that appear in a CLASS statement.
- POLYNOMIAL | POLY is a multivariate polynomial effect in the specified numeric variables.
- SPLINE is a regression spline effect whose columns are univariate spline expansions
of one or more variables. A spline expansion replaces the
original variable with an expanded or larger set of new variables.
- provides the following estimation methods:
- RSPL
- MSPL
- RMPL
- MMPL
- Laplace
- adaptive quadrature
- exercise control over the numerical optimization.
You can choose techniques, update methods, line search algorithms, convergence criteria,
and more. Or, you can choose the default optimization strategies selected for the particular
class of model you are fitting.
- generate variables with SAS programming statements inside of PROC GLIMMIX (except
for variables listed in the CLASS statement).
- grouped data analysis
- obtain separate analyses on observations in groups
- use ODS to create a SAS data set corresponding to any table
- supports ODS Graphics
For further details see the SAS/STAT User's Guide:
The GLIMMIX Procedure
(
PDF | HTML )
Examples
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