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Trouble Replicating Unstructured Mixed Procedure in R

On Tue, 24 Jan 2012, Charles Determan Jr wrote:

            
This is also the Orthodont dataset, distributed with nlme.

As David Atkins pointed out, R defaults to Type I SS. so you would need to 
use, for example, the Anova() command from the car package.  The other 
thing is that the SAS F statistics are only approximate, depending on 
which covariance structure is chosen (perhaps John Maindonald or someone 
clever could comment), so SAS offers different possibilities for ddf eg

http://www2.sas.com/proceedings/sugi26/p262-26.pdf

while lme and lmer offer one or none.

Thread (19 messages)

Charles Determan Jr Trouble Replicating Unstructured Mixed Procedure in R Jan 24 Thompson,Paul Trouble Replicating Unstructured Mixed Procedure in R Jan 24 Charles Determan Jr Trouble Replicating Unstructured Mixed Procedure in R Jan 25 David Atkins Trouble Replicating Unstructured Mixed Procedure in R Jan 25 David Duffy Trouble Replicating Unstructured Mixed Procedure in R Jan 25 John Maindonald Trouble Replicating Unstructured Mixed Procedure in R Jan 25 Charles Determan Jr Trouble Replicating Unstructured Mixed Procedure in R Jan 26 Thompson,Paul Trouble Replicating Unstructured Mixed Procedure in R Jan 26 Luca Borger Trouble Replicating Unstructured Mixed Procedure in R Jan 26 Thompson,Paul Trouble Replicating Unstructured Mixed Procedure in R Jan 26 John Maindonald Trouble Replicating Unstructured Mixed Procedure in R Jan 26 Charles Determan Jr Trouble Replicating Unstructured Mixed Procedure in R Jan 26 Kevin Wright Trouble Replicating Unstructured Mixed Procedure in R Jan 26 John Maindonald Trouble Replicating Unstructured Mixed Procedure in R Jan 26 Charles Determan Jr Trouble Replicating Unstructured Mixed Procedure in R Jan 27 Charles Determan Jr Trouble Replicating Unstructured Mixed Procedure in R Jan 27 iwhite@staffmail.ed.ac.uk Trouble Replicating Unstructured Mixed Procedure in R Jan 27 Steven J. Pierce Trouble Replicating Unstructured Mixed Procedure in R Jan 27 Juliet Hannah Trouble Replicating Unstructured Mixed Procedure in R Jan 27