[Rd] lm considers removed predictors when finding complete cases
Dear R-devel list, I realized that removing a predictor in lm through the "-"'s operator in formula() does not affect the complete cases that are considered. A minimal example is: summary(lm(Wind ~ ., data = airquality)) # 42 observations deleted due to missingness summary(lm(Wind ~ . - Ozone, data = airquality)) # still 42 observations deleted due to missingness, even if only 7 are # missing for the response and the rest of the predictors summary(lm(Wind ~ ., data = subset(airquality, select = -Ozone))) # 7 observations deleted due to missingness I find this behaviour somehow striking and I was wondering whether it is intended, or whether it would be appropriate to document it in lm's help. Any insight on this issue is appreciated. Best regards, -- Eduardo García Portugués Assistant professor Department of Statistics Carlos III University of Madrid Office: 7.3.J21 (Leganés) Phone: (+34) 91624 8836 [[alternative HTML version deleted]] __ R-devel@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-devel
[Rd] abort
FYI. Gábor
❯ R --vanilla -q
> sessionInfo()
R version 3.4.3 (2017-11-30)
Platform: x86_64-apple-darwin15.6.0 (64-bit)
Running under: macOS Sierra 10.12.6
Matrix products: default
BLAS:
/Library/Frameworks/R.framework/Versions/3.4/Resources/lib/libRblas.0.dylib
LAPACK:
/Library/Frameworks/R.framework/Versions/3.4/Resources/lib/libRlapack.dylib
locale:
[1] en_US.UTF-8/en_US.UTF-8/en_US.UTF-8/C/en_US.UTF-8/en_US.UTF-8
attached base packages:
[1] stats graphics grDevices utils datasets methods base
loaded via a namespace (and not attached):
[1] compiler_3.4.3
> conditionCall.x <- function(c) strrep("xxx?", 3000)
> stop(structure(list(message="1"), class=c("x","condition")))
zsh: abort R --vanilla -q
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Re: [Rd] abort
Thanks; fixed in R-devel and R-patched.
Best,
luke
On Tue, 19 Dec 2017, Gábor Csárdi wrote:
FYI. Gábor
❯ R --vanilla -q
sessionInfo()
R version 3.4.3 (2017-11-30)
Platform: x86_64-apple-darwin15.6.0 (64-bit)
Running under: macOS Sierra 10.12.6
Matrix products: default
BLAS:
/Library/Frameworks/R.framework/Versions/3.4/Resources/lib/libRblas.0.dylib
LAPACK:
/Library/Frameworks/R.framework/Versions/3.4/Resources/lib/libRlapack.dylib
locale:
[1] en_US.UTF-8/en_US.UTF-8/en_US.UTF-8/C/en_US.UTF-8/en_US.UTF-8
attached base packages:
[1] stats graphics grDevices utils datasets methods base
loaded via a namespace (and not attached):
[1] compiler_3.4.3
conditionCall.x <- function(c) strrep("xxx?", 3000)
stop(structure(list(message="1"), class=c("x","condition")))
zsh: abort R --vanilla -q
__
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--
Luke Tierney
Ralph E. Wareham Professor of Mathematical Sciences
University of Iowa Phone: 319-335-3386
Department of Statistics andFax: 319-335-3017
Actuarial Science
241 Schaeffer Hall email: luke-tier...@uiowa.edu
Iowa City, IA 52242 WWW: http://www.stat.uiowa.edu
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Re: [Rd] lm considers removed predictors when finding complete cases
> On Dec 19, 2017, at 11:12 AM, EDUARDO GARCIA PORTUGUES > wrote: > > Dear R-devel list, > > I realized that removing a predictor in lm through the "-"'s operator in > formula() does not affect the complete cases that are considered. A minimal > example is: > > summary(lm(Wind ~ ., data = airquality)) > # 42 observations deleted due to missingness > > summary(lm(Wind ~ . - Ozone, data = airquality)) > # still 42 observations deleted due to missingness, even if only 7 are > # missing for the response and the rest of the predictors > > summary(lm(Wind ~ ., data = subset(airquality, select = -Ozone))) > # 7 observations deleted due to missingness > > I find this behaviour somehow striking and I was wondering whether it is > intended, or whether it would be appropriate to document it in lm's help. The behavior in the second instance seems consistent with a desire to compare models (full versus reduced) based on the same data. You expectation appears to be something else but you have not really explained your rationale for a different expectation other than to call it "striking". If by "striking" you mean hitting your head and saying "Oh course, I should have thought of that" then we would be in agreement. -- David. > > Any insight on this issue is appreciated. > > Best regards, > -- > Eduardo García Portugués > Assistant professor > Department of Statistics > Carlos III University of Madrid > > Office: 7.3.J21 (Leganés) > Phone: (+34) 91624 8836 > > [[alternative HTML version deleted]] > > __ > R-devel@r-project.org mailing list > https://stat.ethz.ch/mailman/listinfo/r-devel David Winsemius Alameda, CA, USA 'Any technology distinguishable from magic is insufficiently advanced.' -Gehm's Corollary to Clarke's Third Law __ R-devel@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-devel
