Displaying 20 results from an estimated 7000 matches similar to: "maximizing a likelihood function containing an integral"
2007 Oct 24
1
vectorized mle / optim
Hi the list,
I would need some advice on something that looks like a FAQ: the
possibility of providing vectors to optim() function.
Here is a stupid and short example summarizing the problem:
-------------------------------- example 1 ------------ 8<
----------------------
library(stats4)
data <- rnorm(100,0,1)
lik1 <- function(m, v, data) {
N <- length(data)
lik.mean <-
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:
2010 Feb 09
1
how to adjust the output
Hi R-users,
I have this code below and I understand the error message but do not know how to correct it. My question is how do I get rid of “with absolute error < 7.5e-06” attach to value of cdf so that I can carry out the calculation.
integrand <- function(z)
{ alp <- 2.0165
rho <- 0.868
# simplified expressions
a <- alp-0.5
c1 <-
2013 Apr 09
1
Solving an integral in R gives the error “The integral is probably divergent”
I am trying to solve an integral in R. However, I am getting an error when
I am trying to solve for that integral.
The equation that I am trying to solve is as follows:
$$ C_m = \frac{{abs{x}}e^{2x}}{\pi^{1/2}}\int_0^t t^{-3/2}e^{-x^2/t-t}dt $$
[image: enter image description here]
The code that I am using is as follows:
a <- seq(from=-10, by=0.5,length=100)
## Create a function to compute
2012 Oct 29
0
why isn't integrate function working in a likelihood
Dear R users,
I have been trying to solve for mle's of a function that involves an
integral and I keep getting an error. I created an example to work on first
and even the simple example doesn't give me the mle's. I am getting the
error "Error in integrate(integrand, 0, Inf) : non-finite function value".
I divided my likelihood function into two parts, one part involves
2007 May 24
3
Problem with numerical integration and optimization with BFGS
Hi R users,
I have a couple of questions about some problems that I am facing with
regard to numerical integration and optimization of likelihood
functions. Let me provide a little background information: I am trying
to do maximum likelihood estimation of an econometric model that I have
developed recently. I estimate the parameters of the model using the
monthly US unemployment rate series
2007 Dec 06
1
Integral implicit function
Hi,
Could somebody help me with the following. I want to calculate the integral over an implicit function. I thought to integrate over a function depending on uniroot. In previous topics I found a thread about finding the root of an integral. And that works. But the other way around, does not work. Does R support this?
I included the following example. The function in the example is very easy
2009 Sep 23
1
Numerical integration problem
Hi there
I'm trying to construct a model of mortality risk in 2D space that
requires numerical integration of a hazard function, for which I'm using
the integrate function. I'm occasionally encountering parameter
combinations that cause integrate to terminate with error "Error in
integrate... the integral is probably divergent", which I'm not sure how
to interpret. The
2018 Mar 23
1
Integrate erros on certain functions
In the help for ?integrate:
>When integrating over infinite intervals do so explicitly, rather than
just using a large number as the endpoint. This increases the chance of a
correct answer ? any function whose integral over an infinite interval is
finite must be near zero for most of that interval.
I understand that and there are examples such as:
## a slowly-convergent integral
integrand
2011 Nov 10
2
performance of adaptIntegrate vs. integrate
Dear list,
[cross-posting from Stack Overflow where this question has remained
unanswered for two weeks]
I'd like to perform a numerical integration in one dimension,
I = int_a^b f(x) dx
where the integrand f: x in IR -> f(x) in IR^p is vector-valued.
integrate() only allows scalar integrands, thus I would need to call
it many (p=200 typically) times, which sounds suboptimal. The
2006 Nov 18
1
Questions regarding "integrate" function
Hi there. Thanks for your time in advance.
I am using R 2.2.0 and OS: Windows XP.
My final goal is to calculate 1/2*integral of
(f1(x)^1/2-f2(x)^(1/2))^2dx (Latex codes:
$\frac{1}{2}\int^{{\infty}}_{\infty}
(\sqrt{f_1(x)}-\sqrt{f_2(x)})^2dx $.) where f1(x) and f2(x) are two
marginal densities.
My problem:
I have the following R codes using "adapt" package. Although "adapt"
2011 Mar 29
5
Integration with variable bounds
If this is posted elsewhere I cannot find it. I need to perform multiple
integration where some of the variables are in the bounds of the other
variables. I was trying to use R2Cuba function but cannot set the upper and
lower bounds. My code so far is :
int <- function(y){
u2 = y[1]
z2 = y[2]
u1 =y[3]
z1 = y[4]
ff <- u1*(z1-u1)*u2*(z2-u2)*exp(-0.027*(12-z2))
return(ff)
}
2012 May 23
0
Error from using adaptIntegrate within a function that is then integrated
I want to measure the error in the estimation of a 2 dimensional density
function that is calculated using an integral but run into problems trying
to integrate with adaptIntegrate because the integrand also calls the
function adaptIntegrate. In particular I want
\int \hat{f}(x,y) - f(x,y) dx dy
where \hat{f}(x,y) = \int K(a,b, x, y) da db and in this simulation study I
know what the true value
2010 Dec 22
3
How to integrate a function with additional argument being a vector or matrix?
Dear expeRts,
I somehow don't see why the following does not work:
integrand <- function(x, vec, mat, val) 1 # dummy return value
A <- matrix(runif(16), ncol = 4)
u <- c(0.4, 0.1, 0.2, 0.3)
integrand(0.3, u, A, 4)
integrate(integrand, lower = 0, upper = 1, vec = u, mat = A, val = 4)
I would like to integrate a function ("integrand") which gets an "x" value (the
2010 Oct 29
2
what´s wrong with this code?
Hello, I want to maximize a likelihood function expressed as an
integral that can not be symbolically evaluated. I expose my problem
in a reduced form.
g<- function(x){
integrand<-function(y) {exp(-x^2)*y}
g<-integrate(integrand,0,1)
}
h<-function(x) log((g(x)))
g is an object of the class function, but g(2) is a integrate object,
I can print(g(2))
2002 Jun 28
1
integrate function fails! (PR#1718)
Full_Name: José Enrique Chacón
Version: 1.5.0 and 1.3.1
OS: Windows Millenium
Submission from: (NULL) (158.49.28.155)
Dear reader:
I was trying to evaluate the L2 error produced when estimating the density
function N(0,1) from a sample of size 100 using a kernel density estimate. It
produced a strange value. You can reproduce the process by typing
samp<-rnorm(100)
2008 Feb 15
0
Behaviour of integrate (was 'Poisson-lognormal probability calcul ations')
Hi again,
Adding further information to my own query, this function gets to the core
of the problem, which I think lies in the behaviour of 'integrate'.
-------------------------------------
function (x, meanlog = 0, sdlog = 1, ...) {
require(stats)
integrand <- function(t, x, meanlog, sdlog) dpois(x,t)*dlnorm(t,
meanlog, sdlog)
mapply(function(x, meanlog, sdlog, ...)
#
2008 Feb 18
0
Solved (??) Behaviour of integrate (was 'Poisson-lognormal probab ility calculations')
Hi Again,
I think I've solved my problem, but please tell me if you think I'm wrong,
or you can see a better way!
A plot of the integrand showed a very sharp peak, so I was running into the
integrand "feature" mentioned in the note. I resolved it by limiting the
range of integration as shown here:
--------------------------------------------------
function (x, meanlog = 0,
2012 Oct 19
2
likelihood function involving integration, error in nlm
Dear R users,
I am trying to find the mle that involves integration.
I am using the following code and get an error when I use the nlm function
d<-matrix(c(1,1,0,0,0,0,0,0,2,1,0,0,1,1,0,1,2,2,1,0),nrow=10,ncol=2)
h<-matrix(runif(20,0,1),10)
integ<-matrix(c(0),nrow=10, ncol=2)
ll<-function(p){
for (k in 1:2){
for(s in 1:10){
integrand<-function(x)
2007 Aug 23
1
nls() and numerical integration (e.g. integrate()) working together?
Dear List-Members,
since 3 weeks I have been heavily working on reproducing the results of an
economic paper. The method there uses the numerical solution of an integral
within nonlinear least squares. Within the integrand there is also some
parameter to estimate. Is that in the end possible to implement in R
[Originally it was done in GAUSS]? I'm nearly into giving up.
I constucted an