Displaying 20 results from an estimated 1000 matches similar to: "Non-linear Least Square Optimization -- Function of two variables."
2007 Feb 21
1
Confindence interval for Levenberg-Marquardt fit
Dear all,
I would like to use the Levenberg-Marquardt algorithm for non-linear
least-squares regression using function nls.lm. Can anybody help me to
find a a way to compute confidence intervals on the fitted
parameters as it is possible for nls (using confint.nls, which does not
work for nls.lm)?
Thank you for your help
Michael
2007 Sep 07
2
Matlab's lsqnonlin
Hi! I'm translating some code from Matlab to R and I found a problem.
I need to translate Matlab's function 'lsqnonlin'
(http://www-ccs.ucsd.edu/matlab/toolbox/optim/lsqnonlin.html) into R,
and at the beginning I thought it would be the same as R's 'optim'. But
then I looked at the definition of 'lsqnonlin' and I don't quite see how
to make
2007 Nov 20
1
How is the Gauss-Newton method compared to Levenberg-Marquardt for curve-fitting?
Hi,
It seems to me that the most suitable method in R for curve-fitting is the use of nls, which uses a Gauss-Newton (GN) algorithm, while the use of the Levenberg-Marquardt (LM) algorithm does not seem to be very stressed in R. According to this [1] by Ripley, 'Levenberg-Marquardt is hardly competitive these days' which could imply the low emphasize on LM in R.
The position of LM is, to
2004 Oct 08
0
R interface for MINPACK least squares optimization library
Hello guys.
I've built and uploaded to CRAN an R interface to MINPACK Fortran library,
which solves non-linear least squares problem by modification of the
Levenberg-Marquardt algorithm. The package includes one R function, which
passes all the necessary control parameters to the appropriate Fortran
functions.
The package location is
2004 Oct 08
0
R interface for MINPACK least squares optimization library
Hello guys.
I've built and uploaded to CRAN an R interface to MINPACK Fortran library,
which solves non-linear least squares problem by modification of the
Levenberg-Marquardt algorithm. The package includes one R function, which
passes all the necessary control parameters to the appropriate Fortran
functions.
The package location is
2002 Dec 10
3
clogit and general conditional logistic regression
Can someone clarify what I cannot make out from the
documentation?
The function 'clogit' in the 'survival' package is
described as performing a "conditional logistic regression".
Its return value is stated to be "an object of class clogit
which is a wrapper for a coxph object."
This suggests that its usefulness is confined to the sort of
data which arise in
2008 Mar 13
0
new version of minpack.lm
The package minpack.lm allows nonlinear regression problems to be
addressed with a modification of the Levenberg-Marquardt algorithm based
on the implementation of 'lmder' and 'lmdif' in MINPACK. Version 1.0-8 of
the package is now available on CRAN.
Changes in version 1.0-8 include:
o possibility to obtain standard error estimates on the parameters
via new methods for
2008 Mar 13
0
new version of minpack.lm
The package minpack.lm allows nonlinear regression problems to be
addressed with a modification of the Levenberg-Marquardt algorithm based
on the implementation of 'lmder' and 'lmdif' in MINPACK. Version 1.0-8 of
the package is now available on CRAN.
Changes in version 1.0-8 include:
o possibility to obtain standard error estimates on the parameters
via new methods for
2006 Sep 02
1
nonlinear least squares fitting Trust-Region"
Dear Mr Graves,
Thank you very much for your response. Nobody else from this mailing list ventured to reply to me for the two weeks since I posted my question.
"nlminb" and "optim" are just optimization procedures. What I need is not just optimization, but a nonlinear CURVE FITTING procedure. If there is some way to perform nonlinear curve fitting with the
2011 Oct 31
1
Question on estimating standard errors with noisy signals using the quantreg package
Dear all,
My question might be more of a statistics question than a question on R,
although it's on how to apply the 'quantreg' package. Please accept my
apologies if you believe I am strongly misusing this list.
To be very brief, the problem is that I have data on only a random draw, not
all of doctors' patients. I am interested in the, say, median number of
patients of
2014 Dec 17
2
optimización - resolver sistema - general
Hola a todos,
Simplemente comentar que me tengo encontrado con muchos problemas
de optimización. Mi recomendación general, en el caso multidimensional y
si el tiempo de computación es importante, sería buscar un algoritmo
diseñado para el tipo de problema (evitar los algoritmos más generales
tipo optim si puede haber problemas de mínimos locales). Algunos casos
que tengo resuelto con R
2006 Aug 23
2
nonlinear least squares trust region fitting ?
Hello!
I am running R-2.3.1-i386-1 on Slackware Linux 10.2. I am a former matlab user, moving to R. In matlab, via the cftool, I performed nonlinear curve fitting using the method "nonlinear least squares" with the "Trust-Region" algorithm and not using robust fitting. Is it possible to perform the same analysis in R? I read quite a lot of R documentation, but I could not find
2020 Jul 14
2
How to install libisl.so.19 on chromebook?
I am trying to install minpack.lm on R 3.3.3 (Debian version) on a
Chromebook. But I get this error:
```
> install.packages("minpack.lm")
Installing package into ?/home/marongiuluigi/R/x86_64-pc-linux-gnu-library/3.3?
(as ?lib? is unspecified)
trying URL 'https://cran.rstudio.com/src/contrib/minpack.lm_1.2-1.tar.gz'
Content type 'application/x-gzip' length 43029 bytes
2020 Jul 14
2
How to install libisl.so.19 on chromebook?
Thank you, it looks like I have already libisl:
```
apt search libisl
Sorting... Done
Full Text Search... Done
libisl-dbg/oldstable 0.18-1 amd64
manipulating sets and relations of integer points bounded by linear
constraints
libisl-dev/oldstable 0.18-1 amd64
manipulating sets and relations of integer points bounded by linear
constraints
libisl15/oldstable,now 0.18-1 amd64
2005 Sep 13
4
plot(<lm>): new behavior in R-2.2.0 alpha
As some of you R-devel readers may know, the plot() method for
"lm" objects is based in large parts on contributions by John
Maindonald, subsequently "massaged" by me and other R-core
members.
In the statistics litterature on applied regression, people have
had diverse oppinions on what (and how many!) plots should be
used for goodness-of-fit / residual diagnostics, and to my
2020 Jul 14
1
How to install libisl.so.19 on chromebook?
I don't know about the configuration. I installed R using the standard
protocol for Chromebook
http://blog.sellorm.com/2018/12/20/installing-r-and-rstudio-on-a-chromebook/
the rest, it was done by the system itself...
On Tue, Jul 14, 2020 at 1:30 PM Dirk Eddelbuettel <edd at debian.org> wrote:
>
>
> There is something wrong with your system / setup I did not notice first:
>
2001 Jan 10
2
Levenberg-Marquardt algorithm
Hi All,
Is the Levenberg-Marquardt algorithm available in R. This method combines the
steepest descent algorithm and Newton's method.
Thanks in Advance,
Dermot MacSweeney.
**************************************************************
Dermot MacSweeney NMRC,
Email: dsweeney at nmrc.ucc.ie Lee Maltings,
Tel: +353 21 904178 Prospect Row,
Fax: +353 21 270271 Cork,
WWW:
2009 Jul 07
1
error: no such index at level 2
Hi,
I am confused about how to select elements from a list.
I'm trying to select all rows of a table 'crossRsorted' such that the
mean of a related vector is > 0. The related vector is accessible as
a list element l[[i]] where i is the row index.
I thought this would work:
> crossRsorted[mean(q[[ crossRsorted[,1] ]], na.rm = TRUE) > 0, ]
Error in q[[crossRsorted[, 1]]] :
2005 Feb 11
1
cook's distance in weighted regression
I have a puzzle as to how R is computing Cook's distance in weighted linear
regression.
In
this case cook's distance should be given not as in OLS case by
h_ii*r_i^2/(1-hii)^2 divided by k*s^2 (1)
(where r is plain unadjusted residual, k is number of parameters in model,
etc. )
but rather by
w_ii*h_ii*r_i^2/(1-hii)^2 divided by k*s^2,
2010 Apr 20
1
3D surface plot with wireframe or persp?
Hello Dear,
I have a function, like z=f(x,y), and try a surface plot with this function.
But, on the reference of "wireframe" requires data option, so I generated x
and y, and computed z with them. But, still I have a problem to draw a
surface plot. The code and errors are
##################################################
mle_beta0=64.43707;
mle_beta1=-24365.16;
# generating for