R help - Jan 2004 - Better way to find function

To whom it may concern,

1. I would like to know if there is a command in R to choose a function for 
a given dataset. I am facing a difficult question about how to fit the data 
[ please attachment ]

2. Are there any function that will allow users to do the piecewise 
regression?

If not, is it going to be provide in the new updated version? What I am 
using is the piecewise logistic regression, but it doesn't have a continuous
function though. I hope that R would have a specific command to do the 
piecewise (non)linear regression.

I would apprecaite your suggestion.

Sincerely yours,

Nhum

_________________________________________________________________
Rethink your business approach for the new year with the helpful tips here.

For #1, could you clarify what you mean by `function', an R function, or a
regression function?

For #2, there are several packages on CRAN (and in the R distribution
itself) that fit regression splines, if that's what you meant by `piecewise
regression'.  For logistic regression, you can either use the bs() term in
glm(), or gam() in the `mgcv' package.

HTH,
Andy
> From: nuvo nuvo
> 
> To whom it may concern,
> 
> 1. I would like to know if there is a command in R to choose 
> a function for 
> a given dataset. I am facing a difficult question about how 
> to fit the data 
> [ please attachment ]
> 
> 2. Are there any function that will allow users to do the piecewise 
> regression?
> 
> If not, is it going to be provide in the new updated version? 
> What I am 
> using is the piecewise logistic regression, but it doesn't 
> have a continuous 
> function though. I hope that R would have a specific command 
> to do the 
> piecewise (non)linear regression.
> 
> I would apprecaite your suggestion.
> 
> Sincerely yours,
> 
> Nhum
> 
> _________________________________________________________________
> Rethink your business approach for the new year with the 
> helpful tips here.
> 
> ______________________________________________
> R-help at stat.math.ethz.ch mailing list
> https://www.stat.math.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide! 
> http://www.R-project.org/posting-guide.html
> 
> 

------------------------------------------------------------------------------
Notice:  This e-mail message, together with any attachments,...{{dropped}}

>From: "Liaw, Andy"
   >To: "'nuvo nuvo'" ,r-help at stat.math.ethz.ch
   >Subject: RE: [R] Better way to find function
   >Date: Wed, 21 Jan 2004 09:10:06 -0500
   >
   >For #1, could you clarify what you mean by `function', an R function,
   or a

   >regression function?

   I mean to choose a functional form automatically, e.g. 1/(
   a+exp[b+cx]), a+bx, ... [ I saw some of the commercial software can do
   it ]. 
   >For #2, there are several packages on CRAN (and in the R distribution
   >itself) that fit regression splines, if that's what you meant by
   `piecewise
   >regression'.  For logistic regression, you can either use the bs()
   term in

   >glm(), or gam() in the `mgcv' package.

   I don't want to use Spline, because I need the functional form and
   also parameters. Moreover I have 3 independent variables, not only
   one. 

   I want to do only 2 piecewise regression by using the logistic
   function i.e. c/( 1+exp[a+bx]). Then it will be difficult where to put
   the knot and also it may not be continuous at the knot.
   >
   >HTH,
   >Andy
   >
   > > From: nuvo nuvo
   > >
   > > To whom it may concern,
   > >
   > > 1. I would like to know if there is a command in R to choose
   > > a function for
   > > a given dataset. I am facing a difficult question about how
   > > to fit the data
   > > [ please attachment ]
   > >
   > > 2. Are there any function that will allow users to do the
   piecewise
   > > regression?
   > >
   > > If not, is it going to be provide in the new updated version?
   > > What I am
   > > using is the piecewise logistic regression, but it doesn't
   > > have a continuous
   > > function though. I hope that R would have a specific command
   > > to do the
   > > piecewise (non)linear regression.
   > >
   > > I would apprecaite your suggestion.
   > >
   > > Sincerely yours,
   > >
   > > Nhum
   > >
   > > _________________________________________________________________
   > > Rethink your business approach for the new year with the
   > > helpful tips here.
   > >
   > > ______________________________________________
   > > R-help at stat.math.ethz.ch mailing list
   > > https://www.stat.math.ethz.ch/mailman/listinfo/r-help
   > > PLEASE do read the posting guide!
   > > http://www.R-project.org/posting-guide.html
   > >
   > >
   >
   >
   >---------------------------------------------------------------------
   ---------
   >Notice:  This e-mail message, together with any attachments, contains
   >information of Merck & Co., Inc. (One Merck Drive, Whitehouse
   Station, New
   >Jersey, USA 08889), and/or its affiliates (which may be known outside
   the
   >United States as Merck Frosst, Merck Sharp & Dohme or MSD and in
   Japan, as
   >Banyu) that may be confidential, proprietary copyrighted and/or
   legally
   >privileged. It is intended solely for the use of the individual or
   entity
   >named on this message.  If you are not the intended recipient, and
   have
   >received this message in error, please notify us immediately by reply
   e-mail
   >and then delete it from your system.
   >---------------------------------------------------------------------
   ---------
     _________________________________________________________________

   [1]Learn how to choose, serve, and enjoy wine at Wine @ MSN.

References

   1. http://g.msn.com/8HMBENUS/2749??PS=