All Questions
14
questions
1
vote
0
answers
62
views
converting proc mixed to R [closed]
I have been trying to convert some PROC MIXED SAS code into R, but without success. The code is:
...
- 171
1
vote
1
answer
156
views
Mixed model without fixed intercept- Numerator df for Type II and III ANOVA (lmerTest vs Proc Mixed)
It comes to my attention that there is a discrepancy between lmerTest and Proc Mixed for the numerator degrees of freedom (df) for type II and III ANOVA. This only occurs for mixed model without fixed ...
- 270
1
vote
0
answers
240
views
lmer (R) and proc mixed (SAS)
Recently I have been working on replicating the results from package lmer in R to proc mixed in SAS for mixed modeling. There are multiple model structures that you ...
- 11
0
votes
0
answers
70
views
What is the equivalence of BETWITHIN degrees of freedom in mixed-effect models R?
As in the title. Let's assume I cannot use the Kenward-Roger or Satterthwaite method in mixed-effect models. I was told to use the BETWITHIN method. Now I switched to R. I can use any package I want. ...
- 195
2
votes
0
answers
614
views
Equivalence of proc mixed SAS and R lme/lmer
I am looking at a 2x2 crossover study with period-specific baseline measurements and the according post-treatment outcome values
Intervention (A or B)
Sequence (AB or BA)
Period (visit day1 and visit ...
- 21
4
votes
4
answers
1k
views
Why does lmer (unlike SAS) output a non-zero variance of random effect if it is also included as fixed: (1|site) + site?
(I am completely editing my post. The root question is the same, but I am now posting simulated data to illustrate my issue).
I ran (I beleive) the same model in both proc mixed and R (lmer) but have ...
- 41
1
vote
0
answers
719
views
Multiple nest structure for lme()
I want to build a mixed-effects model with multiple nest structure in R. For example, month nested in year, day nested in year and year. Response variable Y is temperature and predictor variable X is ...
- 11
3
votes
1
answer
1k
views
Fit a linear mixed model with only 1 group
In R, is it possible to force a lmer model with random effect to be fitted on data with only one level? We want to do this to keep the same model structure in rare case where our data only contains 1 ...
3
votes
1
answer
6k
views
glmer in R to recreate GLIMMIX from SAS
I am trying to recreate a PROC GLIMMIX command in R using glmer. Here is a link to the data (from SAS product support GLIMMIX documentation): https://support.sas.com/documentation/cdl/en/statug/63033/...
- 31
2
votes
0
answers
428
views
Convert SAS syntax for mixed models for repeated measures in R
I want to attain a p-value in R using lme4 or nlme which has been obtained from mixed models (...
- 31
1
vote
0
answers
282
views
Specify variance structure TOEP(1) in lmer for mixed model
How can I do the following job in R? More specific: how can I define type=toep(1) in R?
...
- 11
2
votes
0
answers
759
views
Difference in SAS's proc mixed and R's lme4 (Standard Errors/Covariance Structure)
I'm trying to replicate a model created in SAS using lme4 in R.
The SAS Model im using is;
...
- 93
1
vote
0
answers
975
views
Asymptotic covariance matrix of the covariance parameters SAS versus lme
I am trying to obtain the asymptotic covariance matrix of the covariance parameters of a mixed-effects model using SAS and R
In SAS, this matrix can easily be obtained by using the 'asycov' option in ...
- 93
14
votes
2
answers
7k
views
Why does SAS PROC GLIMMIX give me VERY different random slopes than glmer (lme4) for a binomial glmm
I am a user more familiar with R, and have been trying to estimate random slopes (selection coefficients) for about 35 individuals over 5 years for four habitat variables. The response variable is ...
- 565