I am writing to verify the syntax that I am using to test a 3-level
> model with a random intercept at the second level (participant in my
> model) versus a model with a random slope and intercept at this
> level. Specifically, I am testing a 3 level model in which time
> (WEEK) is nested in participants (PARTICIP) and participants are
> nested in dyads (DYADID). The goal is to examine how an
interpersonal > style (CORUMTO) one week predicts changes in depression the
following > week (BDIAFTER) controlling for levels of depression (BDI) from the
> previous week.
>
> I want to verify that the following syntax would be appropriate
> for modeling a random intercept and fixed slope at the participant
> level and a random slope and intercept at the participant level
>
> both<-lme(BDIAFTER~BDI+WEEK+CORUMTO, random=list(DYADID=~1,
> PARTICIP=~CORUMTO), data=weeklydata)
>
>
> Also, when modeling a random slope and intercept at the participant
> level, I receive output, and I also receive the following error
> message?
>
> Warning message
> Fewer observations than random effects in all level 2 groups
>
> I was wondering what this error message means and if it may be
> suggesting that the results after the summary statement are
> incorrect.
>
> I also want to verify that the following syntax is appropriate for
> modeling just a random intercept (and a fixed slope) at the dyad
> and participant levels?
>
> intercept<-lme(BDIAFTER~BDI+WEEK+CORUMTO, random=list(DYADID=~1,
> PARTICIP=~1), data=weeklydata)
>
> Any advice you can give would be much appreciated.
>
> Thank you for your time.
>
> Sincerely,
> Christine Calmes
>
> Christine Calmes, M.A.
> Doctoral Candidate, Clinical Psychology
> University at Buffalo: The State University at New York
> Department of Psychology; Park Hall
> North Campus
> Buffalo NY, 14260
>
>
>