Re: [R] Spline regression (or any localized regression) in the setting of a random effects model.
Also, you might want to check out the gamm4 package.
Ken
On 04/21/14, Bert Gunter wrote:
> See gam() and gamm() in the mgcv package.
>
> Cheers,
> Bert
>
> Bert Gunter
> Genentech Nonclinical Biostatistics
> (650) 467-7374
>
> "Data is not information. Information is not knowledge. And knowledge
> is certainly not wisdom."
> H. Gilbert Welch
>
>
>
>
> On Mon, Apr 21, 2014 at 3:25 PM, John Sorkin
> wrote:
> > Colleagues,
> > Is there any R program that will allow me to run a localized regression
> > (e.g. smoothing spline) in the context of a random effects model? I have
> > data on the growth of animals and want to create growth curves. I am not
> > certain what shape the growth curve would take, so I would like to start
> > with some sort of smoothed (but not "linear") regression to determine the
> > shape of the growth curves. I would like to use a random effects model
> > because I have multiple pairs of observations (age and weight) for each
> > animal. If the shape of the growth curves appear to fit some parametric
> > distribution, I will switch to a parametric model.
> > Thank you,
> > John
> > John David Sorkin M.D., Ph.D.
> > Professor of Medicine
> > Chief, Biostatistics and Informatics
> > University of Maryland School of Medicine Division of Gerontology and
> > Geriatric Medicine
> > Baltimore VA Medical Center
> > 10 North Greene Street
> > GRECC (BT/18/GR)
> > Baltimore, MD 21201-1524
> > (Phone) 410-605-7119
> > (Fax) 410-605-7913 (Please call phone number above prior to faxing)
> >
> > Confidentiality Statement:
> > This email message, including any attachments, is for ...{{dropped:14}}
>
> __
> R-help@r-project.org mailing list
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> PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
> and provide commented, minimal, self-contained, reproducible code.
--
Kenneth Frost
Postdoctoral Research Associate - Dept. of Plant Pathology
University of Wisconsin - Madison
Lab: (608) 262-9914
Mobile: (608) 556-9637
kfr...@wisc.edu
__
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PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.
Re: [R] Spline regression (or any localized regression) in the setting of a random effects model.
See gam() and gamm() in the mgcv package.
Cheers,
Bert
Bert Gunter
Genentech Nonclinical Biostatistics
(650) 467-7374
"Data is not information. Information is not knowledge. And knowledge
is certainly not wisdom."
H. Gilbert Welch
On Mon, Apr 21, 2014 at 3:25 PM, John Sorkin
wrote:
> Colleagues,
> Is there any R program that will allow me to run a localized regression (e.g.
> smoothing spline) in the context of a random effects model? I have data on
> the growth of animals and want to create growth curves. I am not certain what
> shape the growth curve would take, so I would like to start with some sort of
> smoothed (but not "linear") regression to determine the shape of the growth
> curves. I would like to use a random effects model because I have multiple
> pairs of observations (age and weight) for each animal. If the shape of the
> growth curves appear to fit some parametric distribution, I will switch to a
> parametric model.
> Thank you,
> John
> John David Sorkin M.D., Ph.D.
> Professor of Medicine
> Chief, Biostatistics and Informatics
> University of Maryland School of Medicine Division of Gerontology and
> Geriatric Medicine
> Baltimore VA Medical Center
> 10 North Greene Street
> GRECC (BT/18/GR)
> Baltimore, MD 21201-1524
> (Phone) 410-605-7119
> (Fax) 410-605-7913 (Please call phone number above prior to faxing)
>
> Confidentiality Statement:
> This email message, including any attachments, is for ...{{dropped:14}}
__
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.
Re: [R] spline regression
Natural splines (nsin the splines package rcs in the Hmisc or Design package) are linear outside of the range of the knots. You could use those and just specify the knots to be within the portion that you want to allow to be non-linear. Hope this helps, -- Gregory (Greg) L. Snow Ph.D. Statistical Data Center Intermountain Healthcare greg.s...@imail.org 801.408.8111 > -Original Message- > From: r-help-boun...@r-project.org [mailto:r-help-boun...@r- > project.org] On Behalf Of serbring > Sent: Saturday, July 25, 2009 3:29 AM > To: r-help@r-project.org > Subject: [R] spline regression > > > i have a trend that it is linear at first and then it has a particular > trend. > There is a mathematic model, but it describes only the linear part. I > have > tried to use a spline regressione, but i have obtained a particular fit > trend that it is unreal. Can i create a spline regression that it is of > a > unitary degree only at first? > -- > View this message in context: http://www.nabble.com/spline-regression- > tp24656274p24656274.html > Sent from the R help mailing list archive at Nabble.com. > > __ > 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.
