[R-pkgs] Version 0.95-1 of the lme4 package

Douglas Bates bates at stat.wisc.edu
Fri Apr 1 20:19:16 CEST 2005

This may sound like an April Fool's joke but it isn't really.

I just uploaded version 0.95-1 of the lme4 package for R.  This is the 
package with the new versions of the lme (linear mixed-effects) function 
for R and the GLMM (generalized linear mixed models) function.

One distinguishing feature of the 0.95 series of releases of this 
package is the absence of the lme and GLMM functions.  They have been 
replaced by a single function called lmer (pronounced "Elmer").  The 
name could stand for "lme revised" or for "lme for R".

The method of specifying models for lmer is slightly different from that 
for lme, which is the reason for using a new name for this function.  In 
lmer the random effects terms and their grouping factors are specified 
in the formula.  Furthermore, if a family argument is given then a 
generalized linear mixed model is fit - otherwise a linear mixed model 
is fit.

I am writing an article for the next edition of R News describing the 
changes from lme to lmer.  In the meantime you can look at the examples 
and the tests directory of the mlmRev package to see examples of 
specifying lmer models.

My apologies for springing this on the community without warning.  I had 
planned to do a bit more development and create more documentation 
before releasing this new version but yesterday I accidently triggered a 
cascade of inconsistencies by uploading a new version of the Matrix package.

If you are using the current lme4 and prefer not to make changes at this 
time then stay with the 0.9 series of releases and don't update to 0.95-1.

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