Dear Gang,

I have a question regarding running 3dLME. I have two fixed factors of interest (2 categorical variables), and the rest as covariates of no interests (mean centered and quantitative). Because I wanted to see my fixed effects while all of covariates are regressed out, I used 3dLME. MSeq could be like categorical variable (as the values are 1 or -1, but I treat it as quantitative to have a center at 0).

Here is the 3dLME script/specs that I run:

3dLME

-prefix 3dLME_CuexAtt_allCOVs.nii

-jobs 1

-model ‘Cue*Att’
-qVars ‘MSeq,bmi,sTime’
-qVarCenters ‘0,0,0’
-ranEff ‘~1’
-num_glt 14
-gltLabel 1 ‘DvsP’ -gltCode 1 'Cue : 1*D -1

*P MSeq : 0 bmi : 0 sTime : 0’*

-gltLabel 2 ‘VvsN’ -gltCode 2 'Att : 1V -1*N MSeq : 0 bmi : 0 sTime : 0’

-gltLabel 2 ‘VvsN’ -gltCode 2 'Att : 1

…

-dataTable

Subj MSeq bmi sTime Cue Att InputFile

Ss1 1 -0.63657 -1.36364 D V …

Ss2 -1 0.95703 -1.36364 D V…

…

When I only enter MSeq : 0 (e.g., -gltLabel 1 ‘DvsP’ -gltCode 1 ‘Cue : 1*D -1*P MSeq : 0) for each of my glt, the script runs fine. But as I soon as I enter all covariates centered at 0 (as glt specification above, … MSeq : 0 bmi : 0 sTime : 0’), I get the following error message:

Error in seq.default(2, length(sepTerms), 2) :

wrong sign in ‘by’ argument

Calls: process.LME.opts → gl_Constr → glfConstr → seq → seq.default

In addition: Warning messages:

1: In if (is.na(code[[n]][QVpos + 2])) { :

the condition has length > 1 and only the first element will be used

2: In if (QVpos == 1) outList[[1]][[n]] ← NA else outList[[1]][[n]] ← glfConstr(code[[n]][-(QVpos:(QVpos + :

the condition has length > 1 and only the first element will be used

3: In QVpos:(QVpos + 2) :

numerical expression has 3 elements: only the first used

4: In QVpos:(QVpos + 2) :

numerical expression has 3 elements: only the first used

Execution halted

It would be much appreciated if you could provide some help – Or whether I am using a wrong model specification…?

Best,

Michelle.