On Dec 3, 2007 1:45 PM, David Park <[EMAIL PROTECTED]> wrote: > I'm working with Andrew Gelman on a book project and we're having some > difficulties getting coef() to work in some lmer() calls. > > Some versions of the model work and some do not. For example, this works > (in that we can run the model and do coef() from the output): > > R2 <- lmer(y2 ~ factor(z.inc) + z.st.inc.full + z.st.rel.full + (1 + factor( > z.inc) | st.num), family=binomial(link="logit")) > > But this does not (the model runs but coef() doesn't work): > > R3 <- lmer(y2 ~ factor(z.inc) + z.st.inc.full + z.st.rel.full + (1 + z.inc | > st.num ), family=binomial(link="logit")) > > We get the following error: > Error in coef(R3) : unable to align random and fixed effects
Which indicates that the coefficients being estimated for each level of st.num do not correspond to any of the fixed-effects coefficients, hence the coef method, in the sense that it is used in nlme and lme4, cannot be applied. You will need to change the fixed-effects specification so that it includes z.inc. This may mean modifying the contrasts from factor(z.inc). I would suggest switching to polynomial contrasts then replacing the linear term by z.inc > The data are at > http://www.stat.columbia.edu/~gelman/temp/lmerexample.txt<http://www.stat.columbia.edu/%7Egelman/temp/lmerexample.txt> > The file to read the data are at: > http://www.stat.columbia.edu/~gelman/temp/lmerexample.R<http://www.stat.columbia.edu/%7Egelman/temp/lmerexample.txt> > > Any help would be appreciated. > > David K. Park > > -- > David K. Park > Visiting Researcher (Fall 2007 / Spring 2008) > Applied Statistics Center > Columbia University > 1016 Social Work Bldg > (Amsterdam Ave. at 122 St.) > New York, NY 10027 > > Assistant Professor > Department of Political Science > George Washington University > Monroe Hall > 2115 G Street, NW > Washington, D.C. 20052 > http://home.gwu.edu/~dkp/ <http://home.gwu.edu/%7Edkp/> > > Direct: (202) 994-2331 > Dept: (202) 994-6290 > Fax: (202) 994-7743 > > "The great tragedy of Science - the slaying of a beautiful hypothesis > by an ugly fact." > -- Thomas H. Huxley > > [[alternative HTML version deleted]] > > ______________________________________________ > R-help@r-project.org mailing list > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide http://www.R-project.org/posting-guide.html > and provide commented, minimal, self-contained, reproducible code. > ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.