Displaying 20 results from an estimated 2000 matches similar to: "mle (stat4) crashing due to singular Hessian in covariance matrix calculation"
2006 Jun 23
1
How to use mle or similar with integrate?
Hi
I have the following formula (I hope it is clear - if no, I can try to
do better the next time)
h(x, a, b) =
integral(0 to pi/2)
(
  (
    integral(D/sin(alpha) to Inf)
    (
      (
        f(x, a, b)
      )
      dx
    )
  dalpha
)
and I want to do an mle with it.
I know how to use mle() and I also know about integrate(). My problem is
to give the parameter values a and b to the
2007 Aug 13
1
[Fwd: behavior of L-BFGS-B with trivial function triggers bug in stats4::mle]
I sent this in first on 30 July. Now that UseR! is over I'm trying again
(slightly extended version from last time).
 With R 2.5.1 or R 2.6.0 (2007-08-04 r42421)
 "L-BFGS-B" behaves differently from all of the
other optim() methods, which return the value of the function
when they are given a trivial function (i.e., one with no
variable arguments) to optimize.  This is not
a bug in
2010 Jul 31
2
Is profile.mle flexible enough?
Hi the list,
I am experiencing several issues with profile.mle (and consequently with 
confint.mle) (stat4 version 2.9.2), and I have to spend a lot of time to 
find workarounds to what looks like interface bugs. I would be glad to 
get feedback from experienced users to know if I am really asking too 
much or if there is room for improvement.
* Problem #1 with fixed parameters. I can't
2007 Jul 29
1
behavior of L-BFGS-B with trivial function triggers bug in stats4::mle
With the exception of "L-BFGS-B", all of the
other optim() methods return the value of the function
when they are given a trivial function (i.e., one with no
variable arguments) to optimize.  I don't think this
is a "bug" in L-BFGS-B (more like a response to
an undefined condition), but it leads to a bug in stats4::mle --
 a spurious error saying that a better fit
has been
2016 Mar 02
2
ceph and libxl errors attaching device
Dear,
   I need to attach some ceph (0.94.6) block devices to our openstack
(kilo) running instances (xen 4.4) .
   Nova is able to create volumes, attach a detach (alt least there are no
errors)
   The hypervisor can see the blockdevice:
    # rbd -p volumes ls
       volume-xxxxxxxx-7342-434b-9xx1-d046bcxxxxfd
     And the instance xml seems to be ok:
     .................
    <disk
2004 Sep 27
1
Funny behaviour of coef() and vcov() if X is singular
coef() and vcov() have different dimensions if a model contains alised
parameters
as the following example illustrates.
A search on "alised" gave noting as far as I could see.
Is this a known bug?
Bendix C
----------------------
Bendix Carstensen
Senior Statistician
Steno Diabetes Center
Niels Steensens Vej 2
DK-2820 Gentofte
Denmark
tel: +45 44 43 87 38
mob: +45 30 75 87 38
fax: +45
2017 Nov 07
2
Using MLE on a somewhat unusual likelihood function
So I am trying to use the mle command (from stats4 package) to estimate a
number of parameters using data but it keeps throwing up this error message:
Error in solve.default(oout$hessian) :
  Lapack routine dgesv: system is exactly singular: U[1,1] = 0
This error sometimes indicates that the list of starting values is too far
from optimum but this is unlikely since I picked values close to where
2012 Jun 27
4
Intervalos de variable de proporciones, para representar en mapa
Hola.
Tengo que representar en un mapa, valores de proporciones de extranjeros 
con tarjetas de residencia en vigor, según nacionalidad y país de 
procedencia.
Los datos son de este estilo
Rumania
Andalucía    0,200365823
Aragón    0,377192073
Asturias    0,205353012
I. Baleares    0,06592893
Canarias    0,03050312
Cantabria    0,190397393
Castilla-León    0,211670421
Castilla-La Mancha   
2013 May 22
3
definir tipo de variable
Buenos días
¿Podríais explicarme cómo defino en R el tipo de variable y las etiquetas de la misma y las etiquetas de valor?.
En SPSS utilizo la siguiente sintaxis:
VARIABLE LEVEL  DB030(NOMINAL).
VARIABLE LEVEL  DB040(NOMINAL).
VARIABLE LEVEL  DB090(SCALE).
VARIABLE LABELS  DB010 'AÑO'.
VARIABLE LABELS  DB020 'PAÍS'.
VARIABLE LABELS  DB030 'ID_HOGAR'.
VARIABLE
2024 Apr 23
0
System GMM fails due to computationally singular system. Why?
A copy of this question can be found on Cross Validated:
https://stats.stackexchange.com/questions/645610
I am estimating a system of seemingly unrelated regressions (SUR) with
`gmm::sysGmm` in R. Each of the equations has one unique regressor and one
common regressor. The common regressor is a dummy variable indicating the
last observation (n-1 zeros followed by 1). I impose a restriction that
2005 Jul 21
1
About object of class mle returned by user defined functions
Hi,
There is something I don't get with object of class "mle" returned by a 
function I wrote. More precisely it's about the behaviour of method 
"confint" and "profile" applied to these object.
I've written a short function (see below) whose arguments are:
1) A univariate sample (arising from a gamma, log-normal or whatever).
2) A character string
2014 Jan 26
2
[LLVMdev] [llmdev] fail to process llvm generated assembly on windows/mingw32
Hello guys,
I'm using llvm 3.3 on windows with mingw (triple: "i386-unknown-mingw32")
to compile IR code that my
program generates.
I do it in two phases: first I emit assembly code and then assemble it.
       TargetMachine targetMachine =
target.createTargetMachine(triple);
        targetMachine.setAsmVerbosityDefault(true);
        targetMachine.setFunctionSections(true);
    
2012 Feb 28
1
Error in solve.default(res$hessian * n.used) :Lapack routine dgesv: system is exactly singular
Hi there!
I´m a noob when it comes to R and I´m using it to run statisc analysis.
With the code for ARIMA below I´m getting this error: Error in
solve.default(res$hessian * n.used) :Lapack routine dgesv: system is
exactly singular
The code is:
> s.ts <- ts(x[,7], start = 2004, fre=12)
> get.best.arima <- function (x.ts, maxord=c(1,1,1,1,1,1))
+ {
+ best.aic <- 1e8
+ n <-
2008 Sep 12
1
Error in solve.default(Hessian) : system is computationally singular
Hello everyone,
I'm trying to estimate the parameters of the returns series attached using the GARCH code below, but I get the following error message:
Error in solve.default(Hessian) : 
  system is computationally singular: reciprocal condition number = 0
Error in diag(solve(Hessian)) : 
  error in evaluating the argument 'x' in selecting a method for function 'diag'
Can
2010 Jun 04
1
sem R: singular and Could not compute QR decomposition of Hessian
Can somebody help me with the following issue (SEM in R), please:
 
When I run the model (includes second order models) in R, it gives me the following:
 
1)       In sem.default(ram = ram, S = S, N = N, param.names = pars, var.names = vars,  :
  Could not compute QR decomposition of Hessian.
Optimization probably did not converge.
 
2)       I have aliased parameters and NaNS
 
or sometimes when
2007 Sep 26
1
Accessing the fixed- and random-effects variance-covariance matrices of an nlme model
I would appreciate confirmation that the function vcov(model.nlme)  
gives the var-cov matrix of the fixed effects in an nlme model.  
Presumably the random-effects var-cov matrix is given by cov(ranef 
(model.nlme)?
Rob Forsyth
2011 May 18
1
strucchange package Linux help
When I run the code below on Macintosh and Windows, the plot comes out
fine. However, on Linux, the png generated is invalid from R console,
and loading strucchange crashes rkward. Is this a known issue on Linux
and, if so, is there a workaround? Many thanks!
require(strucchange)
data("RealInt")
bp.ri <- breakpoints(RealInt~1, h=15)
summary(bp.ri)
fac.ri <- breakfactor(bp.ri,
2017 Nov 07
0
New vcov(*, complete=TRUE) etc -- coef(<lm>) vs coef(<aov>)
Dear Martin,
I think that your plan makes sense. It's too bad that aov() behaved differently in this respect from lm(), and thus created more work, but it's not be a bad thing that the difference is now explicit and documented.
I expect that that other problems like this will surface, particularly with contributed packages (and I know that you're aware that this has already happened
2009 Nov 24
0
can't use function vcov with a GAMLSS object??
Hi everyone,
 
I''m trying to use function vcov to extract the covariance matrix from a
GAMLSS object. But I''m getting some strange errors and I was hoping someone
could help me out? Vcov works with the same model for lm and glm objects,
but not gamlss objects. I''ve searched various help sites to no avail.
 
Its very possible the reason is that vcov failed though,
2017 Sep 14
0
vcov and survival
Dear Terry,
It's not surprising that different modeling functions behave differently in this respect because there's no articulated standard. 
Please see my response to Martin for my take on the singular.ok argument. For a highly sophisticated user like you, singular.ok=TRUE isn't problematic -- you're not going to fail to notice an NA in the coefficient vector -- but I've