Dear R-users
   
  I am relatively new to R, i hope my many novice questions are welcome.
   
  I have problems accessing some objects (specifically the random effects, correlation structure and variance function) from an object of class gls and lme.
   
  I used the following models:
   
  
  yah <- gls (outcome~ -1 + as.factor(Trial):as.factor(endpoint)+ as.factor(Trial):as.factor(endpoint):trt, data=datt[datt$Trial<4,],
  correlation = corSymm(form=~1|as.factor(Trial)/as.factor(subject)), weights=varIdent(form=~1|endpoint))
   
   
  bm <- lme (outcome~ -1 + as.factor(endpoint)+ as.factor(endpoint):trt, data=datt[datt$Trial<4,],
  random=~-1 + as.factor(endpoint) + as.factor(endpoint):trt|as.factor(Trial),
  correlation = corSymm(form=~1|as.factor(Trial)/as.factor(subject)), weights=varIdent(form=~1|endpoint))
   
  When i print the object "bm" i get the following output:
  ----------------------------------------------------------------------------------------------------------
  > bm 
Linear mixed-effects model fit by REML
  Data: datt[datt$Trial < 4, ] 
  Log-restricted-likelihood: -52.23147
  Fixed: outcome ~ -1 + as.factor(endpoint) + as.factor(endpoint):trt 
    as.factor(endpoint)-1      as.factor(endpoint)1 as.factor(endpoint)-1:trt 
                -3.663087                 -1.772427                 -3.661823 
 as.factor(endpoint)1:trt 
                -3.209671 
   
  Random effects:
 Formula: ~-1 + as.factor(endpoint) + as.factor(endpoint):trt | as.factor(Trial)
 Structure: General positive-definite, Log-Cholesky parametrization
                          StdDev     Corr                  
as.factor(endpoint)-1     2.05744327 as.()-1 as.()1 a.()-1:
as.factor(endpoint)1      0.08400874 -0.976                
as.factor(endpoint)-1:trt 1.90318009  0.975  -0.967        
as.factor(endpoint)1:trt  3.25432832 -0.992   0.982 -0.972 
Residual                  6.48819860   
                      
  Correlation Structure: General
 Formula: ~1 | as.factor(Trial)/as.factor(subject) 
 Parameter estimate(s):
 Correlation: 
  1    
2 0.812
  
Variance function:
 Structure: Different standard deviations per stratum
 Formula: ~1 | endpoint 
 Parameter estimates:
       1       -1 
1.000000 1.764878 
Number of Observations: 18
Number of Groups: 3 
----------------------------------------------------------------------------------------------------
   
  Can somebody tell me how to access the values in blue above? 
   
  Also, when i tried accessing these values i obtained the following
   
   bm$modelStruct
  corStruct  parameters:
[1] -1.394879
varStruct  parameters:
[1] 0.5680815
   
  What do these values represent.
   
  Thanks in advance.. 
  Pryseley
   
   
  sample data:
   
  RowNames Trial subject VISUAL0  TRT VISUAL24 VISUAL52 TREAT outcome endpoint trt 
4      1    1003      65   4       65       55     2       0        1   1 
8      1    1007      67   1       64       68     2      -3        1  -1  
12      2    1110      59   4       53       42     2      -6        1   1  
14      2    1111      64   1       72       65     2       8        1  -1  
16      2    1112      39   1       37       37     2      -2        1  -1   
18      2    1115      59   4       54       58     2      -5        1   1   
24      3    1806      46   4       27       24     2     -19        1   1   
26      3    1813      31   4       33       48     2       2        1   1   
28      3    1815      64   1       67       64     2       3        1  -1 
  4      1    1003      65   4       65       55     2     -10       -1   1     
8      1    1007      67   1       64       68     2       1       -1  -1     
12      2    1110      59   4       53       42     2     -17       -1   1    
14      2    1111      64   1       72       65     2       1       -1  -1    
16      2    1112      39   1       37       37     2      -2       -1  -1   
18      2    1115      59   4       54       58     2      -1       -1   1   
24      3    1806      46   4       27       24     2     -22       -1   1    
26     3    1813      31   4       33       48     2      17       -1   1    
28      3    1815      64   1       67       64     2       0       -1  -1  
   

		
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