nlme

 nlme

ANOVA = lme with no intercepts

Var-cov matrix (positive-definite) for random intercept and slope (G matrix): random=

pdSymm (default,unstructured,MANOVA),pdDiag (diagonal,independent,variance components),pdBlocked (block-diagonal),pdCompSymm (compound symmetry,all cov are equal,exchangeable,sphericity,ANOVA),pdIdent (identical)

sigma matrix for 1st-level residuals:

correlation= corAR1,corARMA,corCAR1,corCompSymm,corSymm (unstructured)

(form = ~ 1 | Subject)

weights = varIdent,varFixed

(form = ~ 1 | age)

gls is lme without the argument “random”

Likelihood ratio comparisons: for comparing random effects,not meaningful for objects fit using REML and with different fixed effects (compared by anova(model), summary(model)).

Defaults: REML, random=list(id=pdsymm), correlation= NULL