Home/ Questions/Resolved the problem of the error in meem(object, conlin, control$niterem) : singularity in backsolve at level 0, block 1
Next
Answered
Adonis O'Kelly
  • 28
Asked: 2022-05-18T19:00:58+00:00 In:

Resolved the problem of the error in meem(object, conlin, control$niterem) : singularity in backsolve at level 0, block 1

  • 28

. Advertisement .

..3..

. Advertisement .

..4..

As advised, I used some code samples in another forum, but it could not improve the problem. My question is the “error in meem(object, conlin, control$niterem) : singularity in backsolve at level 0, block 1” in r – How to solve it? The command line is:

data.frame': 972 obs. of 7 variables:
 $ data_mTBS : num 20.3 22.7 0 47.8 58.7 ...
 $ data_tooth: num 1 1 1 1 1 1 1 1 1 1 ...
 $ Adhesive : Factor w/ 4 levels "C-SE2","C-UBq",..: 2 2 2 2 2 2 2 2 2 2 ...
 $ Approach : Factor w/ 2 levels "ER","SE": 1 1 1 1 1 1 1 1 1 1 ...
 $ Aging : Factor w/ 2 levels "1w","6m": 1 1 1 1 1 1 2 2 2 2 ...
 $ data_name : Factor w/ 40 levels "C-SE2-1","C-SE2-10",..: 11 11 11 11 11 11 11 11 11 11 ...
 $ wait : Factor w/ 2 levels "no","yes": 1 1 1 1 1 1 1 1 1 1 ...
 head(Data)
 
 
  data_mTBS data_tooth Adhesive Approach Aging data_name wait
 1 20.27 1 C-UBq ER 1w C-UBq-1 no
 2 22.73 1 C-UBq ER 1w C-UBq-1 no
 3 0.00 1 C-UBq ER 1w C-UBq-1 no
 4 47.79 1 C-UBq ER 1w C-UBq-1 no
 5 58.73 1 C-UBq ER 1w C-UBq-1 no
 6 57.02 1 C-UBq ER 1w C-UBq-1 no
LME_01<-lme(data_mTBS ~ Adhesive*Approach*Aging*wait, na.action=na.exclude,data = Data, random = ~ 1|data_name);
contrast_Aging<-contrast(LME_01,a = list(Aging =c("1w"),Adhesive = levels(Data$Adhesive),Approach = levels(Data$Approach) ),b = list(Aging =c("6m"), Adhesive = levels(Data$Adhesive),Approach = levels(Data$Approach)))
 
 c1<-as.matrix(contrast$X)
 Contrastsi2<-summary(glht(LME_01, c1))
contrast_Approach<-contrast(LME_01,
  a = list(Approach = c("SE"), Aging =levels(Data$Aging) ,Adhesive = levels(Data$Adhesive)),
  b = list(Approach = c("ER"), Aging =levels(Data$Aging) ,Adhesive = levels(Data$Adhesive)))
 
 c2<-as.matrix(contrast$X)
 Contrastsi3<-summary(glht(LME_01, c2))

and the result:

Error in MEEM(object, conLin, control$niterEM) : Singularity in
  backsolve at level 0, block 1

What does the message mean? Can you advise me to fix it? If you have other better answers, leave them in the answer box below.

mixed-models
Share

1 Answer

  1. Best Answer
    Expert

    The cause: Compared to many other R modeling functions, lme is a little more ignorant or stubborn. These routines either directly notify you when confounded fixed effects are present or discard some of them for you. That is the cause of the “error in meem(object, conlin, control$niterem) : singularity in backsolve at level 0, block 1”.

    You’ll see that knowing wait=="no" is equivalent to knowing Adhesive=="C-UBq"

    Solution:

    Using lme4::lmer will help you.

    library(lme4)
LME_02<-lmer(data_mTBS ~ Adhesive*Approach*Aging*wait+
(1|data_name),
na.action=na.exclude,data = dd)
    • 0

Leave an answer

You must login to add an answer.

Need An Account,