[R-sig-ME] lme, groupedData, random intercept and slope

[David Atkins]

John--

Focusing on the random-effects output (snipped from your post):

Random effects:
  Formula: ~time | Subject
  Structure: General positive-definite
             StdDev       Corr
(Intercept) 6.054897e+00 (Intr)
time        4.160662e-05 1
Residual    9.775954e-04

That is reporting random intercept, random slope (for time), and 
residual error (and that the correlation between intercepts and slopes 
is 1, which usually isn't a good sign...).

Note that those are all on the SD scale (sqrt of variance terms).

If you don't have a copy of Pinheiro and Bates (2000) and plan to use 
nlme, I would strongly suggest tracking one down.

Hope that helps.

cheers, Dave

-- 
Dave Atkins, PhD
Research Associate Professor
Department of Psychiatry and Behavioral Science
University of Washington
datkins at u.washington.edu

Center for the Study of Health and Risk Behaviors (CSHRB)		
1100 NE 45th Street, Suite 300 	
Seattle, WA  98105 	
206-616-3879 	
http://depts.washington.edu/cshrb/
(Mon-Wed)	

Center for Healthcare Improvement, for Addictions, Mental Illness,
   Medically Vulnerable Populations (CHAMMP)
325 9th Avenue, 2HH-15
Box 359911
Seattle, WA 98104
http://www.chammp.org
(Thurs)