Displaying 6 results from an estimated 6 matches similar to: "fitting distributions"
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
2004 Sep 13
2
Problem with mle in stats4 (R 1.9.1)
Hi!
This is a repost of an earlier message (with a clearer example
demonstrating the problem I ran into). If you run the mle example in
stats4
library(stats4)
x <- 0:10
y <- c(26, 17, 13, 12, 20, 5, 9, 8, 5, 4, 8)
ll <- function(ymax=15, xhalf=6)
-sum(stats::dpois(y, lambda=ymax/(1+x/xhalf), log=TRUE))
(fit <- mle(ll))
plot(profile(fit),
2004 Nov 18
1
gibbs sampling for mixture of normals
hi
i'm looking for a gibbs sampling algorithm for R for the case of mixture of K
normals, and in particular for the case of bivariate normals.
i'd be grateful if anyone could send its own R-routine, at least for the
univariate case.
thank you in advance
matteo
2004 Jun 10
1
overhaul of mle
So, I've embarked on my threatened modifications to the mle subset
of the stats4 package. Most of what I've done so far has *not* been
adding the slick formula interface, but rather making it work properly
and reasonably robustly with real mle problems -- especially ones
involving reasonably complex fixed and default parameter sets.
Some of what I've done breaks backward
2004 Aug 09
4
linear constraint optim with bounds/reparametrization
Hello All,
I would like to optimize a (log-)likelihood function subject to a number of
linear constraints between parameters. These constraints are equality
constraints of the form A%*%theta=c, ie (1,1) %*% 0.8,0.2)^t = 1 meaning
that these parameters should sum to one. Moreover, there are bounds on the
individual parameters, in most cases that I am considering parameters are
bound between zero
2004 Sep 15
6
Bessel function
Dear all
Currently, I'm implementing the generalized hyperbolic distribution into
Splus. Unfortunately the Bessel function is not implemented in Splus. In
R the Bessel function does exist but it is an internal function and I'm
not able to look at the code.
Is there any possibility to see the code of the Bessel function in R or
does anybody has an implementation of the Bessel function in