[R-sig-ME] Error in logLik.reStruct(object, conLin) : NA/NaN/Inf in foreign function call (arg 3) when Exponential Correlation added to model

[Esan, Oluwaseun]

Dear List Members,

I am relatively new to R and Mixed Effects Models using LME.

I am unable to post sample data:


I am trying to get the effect of pregnancy on lung function  and age on women with a certain genetic condition. We know lung function declines with age in people with the condition but we do not know the effect pregnancy has on this relationship.

I have repeat measurements of lung function measured up to 4 times in a year for up to 14 years for each woman (A total of 331,722 observations for 11668 women).

I am having problems when trying to add an exponential serial correlation to a validated model.

library(nlme)

covariate 1= age
M1<-lme(lung function~age +covariate1+covariate2+covariate3+ timesincepregnancy ,data=df5,random=~1+age|id, na.action=na.exclude, method ="ML", control=lmeControl(opt='optim'), corr=corExp(form=~age|id, nugget=T))

The following error occurs:

Error in logLik.reStruct(object, conLin) :
  NA/NaN/Inf in foreign function call (arg 3)

When I run it on random sample of 40 women it runs without an error. Is there any further processing I need to do on the data? I have already removed duplicates.

Previous studies have shown exponential correlation structure is the best fit for the data but I cannot seem to get this to work on the dataset I have.

All the best,
Seun


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