[R] Projection pursuit regression method
Hi, list i was trying to do( Projection pursuit regression ) ppr function in Mass library . It is running very good ,no problem ,but when i refered the references Friedman et al 1981 ,,and SMART guide,, i was not able to find how parametes they r geeting using least square method , if any body know how in PPR method we are finding model parameters using least square method ,becoz it seems to a continous function .. thanks in advance anil ANIL KUMAR( METEOROLOGIST) LRF SECTION NATIONAL CLIMATE CENTER ADGM(RESEARCH) INDIA METEOROLOGICAL DEPARTMENT SHIVIJI NAGAR PUNE-411005 INDIA MOBILE +919422023277 [EMAIL PROTECTED] [[alternative HTML version deleted]] __ R-help@stat.math.ethz.ch mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html
Re: [R] Projection Pursuit
Google can be helpful. The 10th hit I got from "projection pursuit regression" is http://www.scs.gmu.edu/~jgentle/csi991/03f/ppreg1024.rtf, which gives some rough outline of the algorithm. If you want more detail, Ripley (1996) PRNN would suffice, I believe. Andy > From: Oliver Lyttelton > > Hello, > > Just a quick question about ppr in library modreg. > > I have looked at Ripley and Venables 2002 and it says that projection > pursuit works "by projecting X in M carefully chosen directions" > > I want to know how it choses the directions? I presume it > moves around the > high-dimensional space of unit vectors finding ones that separate the > response variables, but how. > > I looked at the code, but can't get deeper in than the Fortran call to > Smart. > > I tried to look up Friedman 87, but can't find an electronic > reference. > > Can anyone help, or point me in the direction of an online reference? > > Thanks in advance, > > Oliver Lyttelton > > __ > R-help@stat.math.ethz.ch mailing list > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide! > http://www.R-project.org/posting-guide.html > > > __ R-help@stat.math.ethz.ch mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html
[R] Projection Pursuit
Hello, Just a quick question about ppr in library modreg. I have looked at Ripley and Venables 2002 and it says that projection pursuit works "by projecting X in M carefully chosen directions" I want to know how it choses the directions? I presume it moves around the high-dimensional space of unit vectors finding ones that separate the response variables, but how. I looked at the code, but can't get deeper in than the Fortran call to Smart. I tried to look up Friedman 87, but can't find an electronic reference. Can anyone help, or point me in the direction of an online reference? Thanks in advance, Oliver Lyttelton __ R-help@stat.math.ethz.ch mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html
Re: [R] projection pursuit
This is exactly what I mean by PPDE. I was reading the paper you mention below and I was looking for already implemented code in languages like R, Matlab or C. Thank you all Luis > I don't think anyone has actually answered this. PPDE is a technical > term, defined in > > Friedman, Steutzle and Schroeder (1984) Projection pursuit density > estimation. Journal of the American Statistical Association, > 79(387):599-608, September 1984. > > I don't know of an R implementation, but have known of S ones (to which I > no longer have access). > > If that is not what you mean by PPDE, please give us the reference(s) you > have in mind. > > > On Wed, 17 Mar 2004 [EMAIL PROTECTED] wrote: > > > Does R have a package that performs projection pursuit density estimation? > Or > > anyone knows code in Matlab or C for example to do this? > > > -- > Brian D. Ripley, [EMAIL PROTECTED] > Professor of Applied Statistics, http://www.stats.ox.ac.uk/~ripley/ > University of Oxford, Tel: +44 1865 272861 (self) > 1 South Parks Road, +44 1865 272866 (PA) > Oxford OX1 3TG, UKFax: +44 1865 272595 > > __ [EMAIL PROTECTED] 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
Re: [R] projection pursuit
I don't think anyone has actually answered this. PPDE is a technical term, defined in Friedman, Steutzle and Schroeder (1984) Projection pursuit density estimation. Journal of the American Statistical Association, 79(387):599-608, September 1984. I don't know of an R implementation, but have known of S ones (to which I no longer have access). If that is not what you mean by PPDE, please give us the reference(s) you have in mind. On Wed, 17 Mar 2004 [EMAIL PROTECTED] wrote: > Does R have a package that performs projection pursuit density estimation? Or > anyone knows code in Matlab or C for example to do this? -- Brian D. Ripley, [EMAIL PROTECTED] Professor of Applied Statistics, http://www.stats.ox.ac.uk/~ripley/ University of Oxford, Tel: +44 1865 272861 (self) 1 South Parks Road, +44 1865 272866 (PA) Oxford OX1 3TG, UKFax: +44 1865 272595 __ [EMAIL PROTECTED] 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
RE: [R] projection pursuit
Good point Sean -Original Message- From: [EMAIL PROTECTED] To: '[EMAIL PROTECTED] ' Sent: 3/17/2004 11:51 AM Subject: RE: [R] projection pursuit Yes, xgobi does projection pursuit. Though I'm not so sure about 'projection pursuit density estimation'. Not that I know what that is. -Original Message- From: Davis, Sean (NIH/NHGRI) [mailto:[EMAIL PROTECTED] Sent: Wednesday, March 17, 2004 10:44 AM To: '[EMAIL PROTECTED] '; '[EMAIL PROTECTED] ' Subject: RE: [R] projection pursuit Luis, If I am not mistaken, the xgobi package (which requires xgobi executable) does interactive projection pursuit. Others can correct me if I'm wrong and there may be other packages, as well. Sean -Original Message- From: [EMAIL PROTECTED] To: [EMAIL PROTECTED] Sent: 3/17/2004 9:59 AM Subject: [R] projection pursuit Dear helpers Does R have a package that performs projection pursuit density estimation? Or anyone knows code in Matlab or C for example to do this? Thank you all Luis __ [EMAIL PROTECTED] 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 __ [EMAIL PROTECTED] 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 __ [EMAIL PROTECTED] 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 __ [EMAIL PROTECTED] 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
RE: [R] projection pursuit
Yes, xgobi does projection pursuit. Though I'm not so sure about 'projection pursuit density estimation'. Not that I know what that is. -Original Message- From: Davis, Sean (NIH/NHGRI) [mailto:[EMAIL PROTECTED] Sent: Wednesday, March 17, 2004 10:44 AM To: '[EMAIL PROTECTED] '; '[EMAIL PROTECTED] ' Subject: RE: [R] projection pursuit Luis, If I am not mistaken, the xgobi package (which requires xgobi executable) does interactive projection pursuit. Others can correct me if I'm wrong and there may be other packages, as well. Sean -Original Message- From: [EMAIL PROTECTED] To: [EMAIL PROTECTED] Sent: 3/17/2004 9:59 AM Subject: [R] projection pursuit Dear helpers Does R have a package that performs projection pursuit density estimation? Or anyone knows code in Matlab or C for example to do this? Thank you all Luis __ [EMAIL PROTECTED] 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 __ [EMAIL PROTECTED] 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 __ [EMAIL PROTECTED] 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
RE: [R] projection pursuit
Luis, If I am not mistaken, the xgobi package (which requires xgobi executable) does interactive projection pursuit. Others can correct me if I'm wrong and there may be other packages, as well. Sean -Original Message- From: [EMAIL PROTECTED] To: [EMAIL PROTECTED] Sent: 3/17/2004 9:59 AM Subject: [R] projection pursuit Dear helpers Does R have a package that performs projection pursuit density estimation? Or anyone knows code in Matlab or C for example to do this? Thank you all Luis __ [EMAIL PROTECTED] 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 __ [EMAIL PROTECTED] 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
[R] projection pursuit
Dear helpers Does R have a package that performs projection pursuit density estimation? Or anyone knows code in Matlab or C for example to do this? Thank you all Luis __ [EMAIL PROTECTED] 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
