[R] empirical (sandwich) SE estimate in lme ()?

[Na Li]

Is it possible to get the empirical (sandwich) S.E. estimates for the
fixed effects in lme () (thus allowing possibly correlated errors within
the group)? In SAS you can get it by the 'empirical' option to PROC MIXED.

Cheers,

Michael

-- 
Na (Michael) Li, Ph.D.               
Division of Biostatistics          A443 Mayo Building, MMC 303   
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