Displaying 20 results from an estimated 2000 matches similar to: "negative multinomial regression models"
2010 Jul 05
2
Function to compute the multinomial beta function?
Dear R-users,
Is there an R function to compute the multinomial beta function? That is, the normalizing constant that arises in a Dirichlet distribution. For example, with three parameters the beta function is Beta(n1,n2,n2) = Gamma(n1)*Gamma(n2)*Gamma(n3)/Gamma(n1+n2+n3)
Thanks in advance for any assisstance.
Regards,
Greg
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2009 Dec 15
3
RFC: lchoose() vs lfactorial() etc
lgamma(x) and lfactorial(x) are defined to return
ln|Gamma(x)| {= log(abs(gamma(x)))} or ln|Gamma(x+1)| respectively.
Unfortunately, we haven't chosen the analogous definition for
lchoose().
So, currently
> lchoose(1/2, 1:10)
[1] -0.6931472 -2.0794415 NaN -3.2425924 NaN -3.8869494
[7] NaN -4.3357508 NaN -4.6805913
Warning message:
In
2007 Oct 26
5
help
hello,
please can anyone help me out. Am a new user of R
program. Am having problem
with this code below, not getting the expected
results.
1. Each m, the cumulative sum should be 1.000 but the
2nd and 3rd m returned 2.000 and 3.000
instead of 1.000.
2. to get the LCL(m) and UCL(m) for each m base on
these instructions
if out.cum > 0.025 then LCL(m)= y-1
if out.cum >0.975
2007 Oct 29
2
help please
hello,
please can anyone help me out. Am a new user of R
program. Am having problem
with this code below, not getting the expected
results.
Each m, the cumulative sum should be 1.000 but the
2nd and 3rd m returned 2.000 and 3.000
instead of 1.000.
thanks
Aruike
pp=function(x,n,M){z=1.0;a=2.3071430;b=7.266064;H=3
out.h=c()
out.y=c()
out.m=c()
out.prob=c()
2011 Aug 17
1
multinomRob - error message
Hi,
I would like to use the multinomRob function to test election results.
However, depending on which independent variables I include and how
many categories I have in the dependent variable, the model cannot be
estimated.
My data look like this (there are 68 observations):
> head(database)
RESTE09 GAUCHE09 PDC09 PLR09 UDC09 MCG09 RESTE05 GAUCHE05 PDC05
D1 1455
2006 Jul 22
1
ifelse command
Dear:
I try to revise the maximum likelihood function below using something constrains. But it seems something wrong with it. Becasue R would not allow me to edit the function like this. It is very appreciate if you can help.
function (parameters,y,x1,x2)
{
p<-parameters[1]
alpha1<-parameters[2]
beta1<-parameters[3)]
delta1<-parameters[4]
alpha2<-parameters[5]
2005 Jul 03
2
over/under flow
I am porting some FORTRAN to R in which an Inf triggers an if(). The
trigger is infinite on exp(lgamma(OVER)). What is the canonical R
style of determining OVER when exp(OVER)== Inf? The code structure
that I am
porting is best left intact--so I need to query R somehow to the value
of OVER that causes exp(lgamma(OVER)) to equal Inf.
On my system,
exp(lgamma(171)) is about first to equal Inf.
2009 Apr 22
2
integrate lgamma from 0 to Inf
Dear R users,
i try to integrate lgamma from 0 to Inf. But here i get the message "roundoff error is detected in the extrapolation table", if i use 1.0e120 instead of Inf the computation works, but this is against the suggestion of integrates help information to use Inf explicitly. Using stirlings approximation doesnt bring the solution too.
## Stirlings approximation
lgammaApprox
1998 Sep 10
2
R-beta: trouble compiling 0.62.3 on SunOS 4.1.4: lgamma conflicts
I've recently tried to get 0.62.3 up on our Suns (4.1.4, using gcc; I'm
also having trouble with a Solaris 2.6 compile but I haven't given up hope
on that one yet) -- the last compile I did was 0.61.1, which worked
smoothly.
Running
./configure --prefix=/usr/local/apps/R/R-0.62.3 [--with-g77]
(tried both with and without g77, eventually get to the same place),
I get a conflict
2012 Oct 05
2
problem with convergence in mle2/optim function
Hello R Help,
I am trying solve an MLE convergence problem: I would like to estimate
four parameters, p1, p2, mu1, mu2, which relate to the probabilities,
P1, P2, P3, of a multinomial (trinomial) distribution. I am using the
mle2() function and feeding it a time series dataset composed of four
columns: time point, number of successes in category 1, number of
successes in category 2, and
2008 Apr 18
3
help me to debug this part of code?
I am trying to solve the integration equation, for different values of K from
4 to 25, the integration is with respect to u,
Here is the equation: gamma(k/2) / ( sqrt(k-1)*gamma((k-1)/2) ) *
integrate(f= (1+u^2/k-1)^(-k/2), lower=0, upper= sqrt(a^2*k/(k+1-a^2)) ) =
the similar expression as te left hand except k becomes k+1
my code is below, I don't know why R keep telling me the syntax
2004 Jun 26
1
S4 group "Math", "getGroupMembers", "genericForPrimitive"
Hi,
I found the following on Windows 2000/NT
R Version 1.9.1 (2004-06-21) (also Version 1.9.0):
The S4 group "Math" doesn't work as documented; i.e., "log", "log10",
"gamma" and "lgamma" are included
in the documentation but don't work. See example code below.
Moreover, what about 'genericForPrimitive' which is used
in
2002 Jan 16
1
factorials
I'm a total newbie at using R, and so there probably
is a better way to do this. However, I couldn't find
one, and so maybe this will help someone.
I was calculating log-likelihoods using a multinomial
model, and found that for large n, prod(n:1) wouldn't
work to calculate factorials (e.g., prod(200:1) =
Inf). The below function calculates the natural log
of a factorial (e.g.
2006 Jul 22
1
Why the contrain does not work for selecting a particular range of data?
Dear:
Continuing the issue of 'ifelse'! I selecting the data whose 'x2'=1 for maximizing likelihood. I used two way to do this but the results are different.
1.Way one I use the data for x2=1 and run the program. It works for me. Tthe program is described as below:
function (parameters,y1,x11)
{
p<-parameters[1]
alpha1<-parameters[2]
beta1<-parameters[3]
2014 Sep 22
2
Replace isnan and lgamma in Fortran subroutine in R package
Hello,
I submitted a package which used Fortran functions isnan and lgamma. However, I was told that:
isnan and lgamma are not Fortran 95 functions.
I was asked to write 'cross-platform portable code' and so should not be writing GNU extensions to Fortran.
See http://cran.r-project.org/web/checks/check_results_mpath.html, which will shortly show installation failures under Solaris.
I
2011 Aug 02
1
My R code is not efficient
Dear R users,
I have two n*1 integer vectors, y1 and y2, where n is very very large.
I'd like to compute
elbp = 4^(y1) * 5^(y2) * sum_{i=0}^{max(y1, y2)} [{ (y1-i)! * (i)! *
(y2-i)! }^(-1)];
that is, I need to compute "elbp" for each (y1, y2) pair.
So I made R code like below, but I don't think it's efficient
Would you plz tell me how to avoid this "for"
2005 Nov 21
2
Multinomial Nested Logit package in R?
Dear R-Help,
I'm hoping to find a Multinomial Nested Logit package in R. It would
be great to find something analogous to "PROC MDC" in SAS:
> The MDC (Multinomial Discrete Choice) procedure analyzes models
> where the
> choice set consists of multiple alternatives. This procedure
> supports conditional logit,
> mixed logit, heteroscedastic extreme value,
2005 Nov 10
2
Help to multinomial analyses
Dear Sirs,
Could you please be so kind as to send us some information on residuals in
multinomial logistic models? Is it possible to use R software?
We thank you in advance.
Sincerely yours
Luciana Alves,MSc
Beatriz Leimann, MD
--
Luciana Correia Alves
Doutoranda em Sa??de P??blica
ENSP - Fiocruz
2002 Dec 22
1
lgamma(-0.8)=?
Dear R users:
I wonder anyone is aware of such a thing from lgamma()
> lgamma(-0.8)
[1] 1.747207
I thought it should be NA as in S-PLUS. Both R-1.3.1 and R-1.5.1
report this result. I don't have the latest R-1.6.1 so I don't
know whether this is corrected or not.
Happy holidays,
Paul.
2006 Feb 22
3
multinomial test
Hi All,
What is the R function for computing multinomial distribution, e.g. f(2,1,3; 2/9, 1/6, 11/18, 6)?
That is, a total of 6 trials, event 1's p1=2/9, x1=2, event 2's p2=1/6, x2=1, and event 3's p3=11/18, x3=3.
thanks,
Johnny
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