[R-sig-ME] Convergence in lme4: Something in the documentation

[Simon Harmel]

Thank you, Ben!

On Sat, Nov 14, 2020 at 3:11 PM Ben Bolker <bbolker using gmail.com> wrote:

>   The problem here is that some of your pars values are negative, so
> you're giving runif() a {min,max} pair that are in the wrong order.
> Maybe:
>
>    mins <- pmin(pars/1.01, pars*1.01)
>    maxs <- pmax(pars/1.01, pars*1.01)
>   runif(length(pars),mins, maxs)
>
>   will do what you want.
>
> On Sat, Nov 14, 2020 at 4:02 PM Simon Harmel <sim.harmel using gmail.com> wrote:
> >
> > Dear All,
> >
> > This page (
> http://search.r-project.org/R/library/lme4/html/convergence.html)
> > does a fantastic job of explaining how to possibly overcome/explore the
> > lack of convergence in lme4 models.
> >
> > However, I have a question about item "#4 restart the fit from the
> original
> > value".
> >
> > For my `lmer()` model, the `getME(fiitted_model,"theta")` returns:
> >
> > pars = c(0.55714322,  0.04364260, -0.00577823,  0.35910270, -0.03138007,
> >  0.02750460)
> >
> > Following the documentation, when I then do:
> >
> > (pars_x <- runif(length(pars), pars/1.01, pars*1.01)), I get:
> >
> > [1] 0.55558159 0.04369471        NaN 0.36202453        NaN 0.02732069
> > Warning message:
> > In runif(length(pars), pars/1.01, pars * 1.01) : NAs produced
> >
> > These NaN will mess up the next steps. Is there a solution to this?
> >
> > Simon
> >
> >         [[alternative HTML version deleted]]
> >
> > _______________________________________________
> > R-sig-mixed-models using r-project.org mailing list
> > https://stat.ethz.ch/mailman/listinfo/r-sig-mixed-models
>

	[[alternative HTML version deleted]]