[R] weighted regression inside FOREACH loop

Thierry Onkelinx thierry.onkelinx at inbo.be
Fri Oct 7 15:47:14 CEST 2016

Dear Roger,

Maybe you want to return(mod) instead of return(mod$coef)

Best regards,

ir. Thierry Onkelinx
Instituut voor natuur- en bosonderzoek / Research Institute for Nature and
team Biometrie & Kwaliteitszorg / team Biometrics & Quality Assurance
Kliniekstraat 25
1070 Anderlecht

To call in the statistician after the experiment is done may be no more
than asking him to perform a post-mortem examination: he may be able to say
what the experiment died of. ~ Sir Ronald Aylmer Fisher
The plural of anecdote is not data. ~ Roger Brinner
The combination of some data and an aching desire for an answer does not
ensure that a reasonable answer can be extracted from a given body of data.
~ John Tukey

2016-10-07 15:24 GMT+02:00 Bos, Roger <roger.bos op rothschild.com>:

> I have a foreach loop that runs regressions in parallel and works fine,
> but when I try to add the weights parameter to the regression the
> coefficients don’t get stored in the “models” variable like they are
> supposed to.  Below is my reproducible example:
> library(doParallel)
> cl <- makeCluster(4)
> registerDoParallel(cl)
> fmla <- as.formula("y ~ .")
> models <- foreach(d=1:10, .combine=rbind, .errorhandling='remove') %dopar%
> {
>   datdf <- data.frame(y = 1:100+2*rnorm(100), x = 1:100+rnorm(100))
>   weights <- rep(c(1,2), 50)
>   mod <- lm(fmla, data=datdf, weights=weights)
>   #mod <- lm(fmla, data=datdf)
>   return(mod$coef)
> }
> models
> You can change the commenting on the two “mod <-“ lines to see that the
> non-weighted one works and the weighted regression doesn’t work.  I tried
> using .export="weights" in the foreach line, but R says that weights is
> already being exported.
> Thanks in advance for any suggestions.
> ***************************************************************
> This message and any attachments are for the intended recipient's use only.
> This message may contain confidential, proprietary or legally privileged
> information. No right to confidential or privileged treatment
> of this message is waived or lost by an error in transmission.
> If you have received this message in error, please immediately
> notify the sender by e-mail, delete the message, any attachments and all
> copies from your system and destroy any hard copies.  You must
> not, directly or indirectly, use, disclose, distribute,
> print or copy any part of this message or any attachments if you are not
> the intended recipient.
> ______________________________________________
> R-help op r-project.org mailing list -- To UNSUBSCRIBE and more, see
> 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.

	[[alternative HTML version deleted]]

More information about the R-help mailing list