Displaying 20 results from an estimated 700 matches similar to: "maxNR in maxLik package never stops"
2010 Mar 12
2
Question regarding to maxNR
Hi R-users,
Recently, I use maxNR function to find maximizer. I have error appears as follows
Error in maxNRCompute(fn = fn, grad = grad, hess = hess, start = start, :
NA in the initial gradient
My code is
mu=2
s=1
n=300
library(maxLik)
set.seed(1004)
x<-rcauchy(n,mu,s)
loglik<-function(mu)
{
log(prod(dcauchy(x,mu,s)))
}
maxNR(loglik,start=median(x))$estimate
Does anyone know how
2010 Mar 22
1
maxNR - Error in p(a, b) : element 1 is empty; the part of the args list of '*' being evaluated was: (b, t)
Hello everyone...
We were trying to implement the Newton-Raphson method in R, and estimate the
parameters a and b, of a function, F, however we can't seem to implement
this the right way. Hope you can show me the right way to do this. I think
what we want R to do is to read the data from the website and then peform
maxNR on the function, F. Btw the version of R being used is "RGui for
2011 Jun 06
2
Taking Integral and Optimization using Integrate, Optim and maxNR
Dear All, Hello!
I have some questoins in R programming as follows:
Question 1- How to take the integral of this function with respect to y, such that x would appear in the output after taking integral.
f(x,y)=(0.1766*exp(-exp(y+lnx))*-exp(y+lnx))/(1-exp(-exp(y+lnx))) y in (-6.907,-1.246)
It is doable in maple but not in R. At least I could not find the way.
p.s: result from maple is:
2007 Oct 30
2
Splitting up the micEcon package?
Dear R Users:
The functions of our "micEcon" package [1,2] can be subdivided into three
categories:
- microeconomic demand and firm models
- sample selection models (mainly selection())
- routines for (likelihood) maximisation (e.g. maxLik(), maxNR(), maxBHHH())
(mainly used for ML estimation of sample selection models)
Although sample selection models are often used in
2020 Oct 09
1
[External] Re: unable to access index for repository...
>>>>> Steven Yen
>>>>> on Fri, 9 Oct 2020 05:39:48 +0800 writes:
> Oh Hi Arne, You may recall we visited with this before. I
> do not believe the problem is algorithm specific. The
> algorithms I use the most often are BFGS and BHHH (or
> maxBFGS and maxBHHH). For simple econometric models such
> as probit, Tobit, and evening
2010 Oct 01
1
Place constrictions on parameters when using Optim and MaxLik
Hi R users,
I am trying to restrct the range of two of the parameters in a maximization
problem. Both parameters should be between -1 and 1. As far as I know, if
I choose the estimation method ="L-BFGS-B" under Optim, I can restrict the
parameter space. However, the "L-BFGS-B" always require finite values of
the loglik function and cannot get around of the problem if an
2010 Sep 14
2
Can I monitor the iterative/convergence process while using Optim or MaxLik?
Hi R-helpers,
Is it possible that I have the estimates from each step/iteration shown on
the computer screen in order to monitor the process while I am using Optim
or MaxLik?
Thanks for your help.
Maomao
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2009 May 16
1
maxLik pakage
Hi all;
I recently have been used 'maxLik' function for maximizing G2StNV178 function with gradient function gradlik; for receiving this goal, I write the following program; but I have been seen an error in calling gradient function;
The maxLik function can't enter gradlik function (definition of gradient function); I guess my mistake is in line ******** ,that the vector ‘h’ is
2009 May 11
1
maxLik package
Hi all.
Recently i have been used maxlik package for optimizing a function with 5 parameters but i couldn't define gradient argument in function maxLik;
How i can define a command to receive my goal? Whether I can change the core of this package?
Thanks for your attention and reply
A. kheradmandi
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2011 Jul 12
1
LOESS function Newton optimization
I have a question about running an optimization function on an existing LOESS
function defined in R. I have a very large dataset (1 million observations)
and have run a LOESS regression. Now, I want to run a Newton-Raphson
optimization to determine the point at which the slope change is the
greatest.
I am relatively new to R and have tried several permutations of the maxNR
and nlm functions with
2010 Mar 27
1
R runs in a usual way, but simulations are not performed
Dear addresses, I need perform a batch of 10 000 simulations for each of
4 options considered. (The idea is to obtain the parameter estimates in
a heteroskedastic linear regression model - with additive or mixed
heteroskedasticity - via the Kenward-Roger small-sample adjusted
covariance matrix of disturbances). For this purpose I wrote an R
program which would capture all possible options (true
2011 Feb 07
2
fast optimization routines in R
Dear R help archive group,
I am looking for a maximization routine that I can use to maximize a large
variety of relatively complex likelihoods. I undertand (from previous posts)
that coding the objective function more efficiently can help. However, the
optimization routine employed seems important too. So far, I have tried the
optimization routines optim, maxlik, trust and nlminb. The latter two
2010 May 10
2
Robust SE & Heteroskedasticity-consistent estimation
Hi,
I'm using maxlik with functions specified (L, his gradient & hessian).
Now I would like determine some robust standard errors of my estimators.
So I 'm try to use vcovHC, or hccm or robcov for example
but in use one of them with my result of maxlik, I've a the following
error message :
Erreur dans terms.default(object) : no terms component
Is there some attributes
2009 Mar 23
4
newton method
Hi R-users,
Does R has a topic on newton's method?
Thank you for the info.
2008 Jun 08
2
optim, constrOptim: setting some parameters equal to each other
Hello, and apologies for the upcoming naive questions. I am a biologist who is trying to teach himself the appropriate areas of math and stats. I welcome pointers to suggested background reading just as much as I do direct answers to my question.
Let's say I have a function F() that takes variables (a,b,c,a1,b1,c1) and returns x, and I want to find the values of these variables that result in
2011 Apr 10
0
maxLik package.
Dear Sir/ Madam,
I have some enquiry in R about maxLik package where, in this package we have the
usage
maxLik(logLik, grad, hess, start, method, iterlim, print.level) when I used
this with print.level equals to 3 I could have estimates of parameters at each
iteration but I do not know how can I call the information in the level. Is
there any way can help me to call the information within
2008 Mar 07
0
Packages micEcon, sampleSelection, and maxLik
Dear R Users:
We have splitted up the micEcon package into three packages:
a) Package "maxLik" provides tools for maximum likelihood estimations
(see http://www.maxLik.org).
b) Package "sampleSelection" provides tools for estimating Heckman-type sample
selection/generalized tobit models (see http://www.sampleSelection.org).
c) Package "micEcon" contains the
2008 Mar 07
0
Packages micEcon, sampleSelection, and maxLik
Dear R Users:
We have splitted up the micEcon package into three packages:
a) Package "maxLik" provides tools for maximum likelihood estimations
(see http://www.maxLik.org).
b) Package "sampleSelection" provides tools for estimating Heckman-type sample
selection/generalized tobit models (see http://www.sampleSelection.org).
c) Package "micEcon" contains the
2020 Oct 08
0
[External] Re: unable to access index for repository...
Oh Hi Arne,
You may recall we visited with this before. I do not believe the problem is algorithm specific. The algorithms I use the most often are BFGS and BHHH (or maxBFGS and maxBHHH). For simple econometric models such as probit, Tobit, and evening sample selection models, old and new versions of R work equally well (I write my own programs and do not use ones from AER or sampleSekection).
2020 Oct 08
2
[External] Re: unable to access index for repository...
Hi Steven
Which optimisation algorithms in maxLik work better under R-3.0.3 than
under the current version of R?
/Arne
On Thu, 8 Oct 2020 at 21:05, Steven Yen <styen at ntu.edu.tw> wrote:
>
> Hmm. You raised an interesting point. Actually I am not having problems with aod per se?-it is just a supporting package I need while using old R. The essential package I need, maxLik, simply