Displaying 20 results from an estimated 3000 matches similar to: "Goodness of fit to Poisson / NegBinomial"
2001 Feb 08
2
dnbinom(,size<1,)=0 (PR#842)
This came up on r-help but indicates a bug.
dnbinom(x,n,p) calls dbinom_raw(n-1,...)
which returns 0 for n<1.
-thomas
---------- Forwarded message ----------
Date: Thu, 08 Feb 2001 17:10:23 +0000
From: Yudi Pawitan <yudi@stat.ucc.ie>
To: Mark Myatt <mark@myatt.demon.co.uk>
Cc: R-Help <r-help@stat.math.ethz.ch>
Subject: Re: [R] Goodness of fit to Poisson / NegBinomial
2009 Oct 26
2
basic statistics to csv
I know that my question is like a very newbie question, but at the moment
I stacked with it and I need a quick solution. I need to make an overall
statistical overview of various datasets, the summary() and numSummary()
functions are fully sufficient. My question is, how can I export results
to a spreadsheet-like file, as a .csv. For the summary() with an "x"
dataset I can use this way:
2008 Feb 10
1
Error while using fitdistr() function or goodfit() function
Try changing your method to "ML" and try again. I tried the run the
first example from the documentation and it failed with the same error.
Changing the estimation method to ML worked.
@List: Can anyone else verify the error I got? I literally ran the
following two lines interactively from the example for goodfit:
dummy <- rnbinom(200, size = 1.5, prob = 0.8)
gf <- goodfit(dummy,
2008 Apr 18
2
rzinb (VGAM) and dnbinom in optim
Dear R-help gurus (and T.Yee, the VGAM maintainer) -
I've been banging my head against the keyboard for too long now, hopefully someone can pick up on the errors of my ways...
I am trying to use optim to fit a zero-inflated negative binomial distribution. No matter what I try I can't get optim to recognize my initial parameters. I think the problem is that dnbinom allows either
2009 Oct 20
1
kendall.global
Hi every body:
I need some help with kendall.global. The example in the manual seems not working well, and cannot used with my data, always the same error.
data(mite)
> mite.hel <- decostand(mite, "hel")
>
> # Reproduce the results shown in Table 2 of Legendre (2005), a single group
> mite.small <- mite.hel[c(4,9,14,22,31,34,45,53,61,69),c(13:15,23)]
>
2005 Apr 14
1
weird problem with "access denied" on share
Hi folks,
I am having a weird problem that I just recently noticed on this
particular server runnng Samba 3.0.10 on Fedora Core 3 and am hoping
someone could shed some light on this.
We're using tdb for our backend database.
The user "nsu" is a member of unix group admin.
The unix group admin is mapped to "Domain Adminstrators".
This works OK, in that when logging in
2009 Mar 02
2
Unrealistic dispersion parameter for quasibinomial
I am running a binomial glm with response variable the no of mites of two
species y->cbind(mitea,miteb) against two continuous variables (temperature
and predatory mites) - see below. My model shows overdispersion as the
residual deviance is 48.81 on 5 degrees of freedom. If I use quasibinomial
to account for overdispersion the dispersion parameter estimate is 2501139,
which seems
2011 Aug 20
4
I have a problem with R!!
Dear all
i?m working with a program i?ve made in R (using functions that others
created)
to run my program i need a sample. if i generate the sample using for
example, rnorm(n, mu, sigma) i have no problem
but if i obtain a sample from a column in excel and i copy it, the program
says that there is a mistake: it says "Error en `[.data.frame`(data,
indices) : undefined columns
2011 Nov 17
3
Named rows in a table (data frame) read from a file
I read a table as follows:
> F1 <- read.table("Rtext3.txt")
> F1
Price Floor Area Rooms Age Cent.heat
a 52.00 111 830 5 6.2 no
b 54.75 128 710 5 7.5 no
c 57.50 101 1000 5 4.2 no
d 57.50 131 690 6 8.8 no
e 59.75 93 900 5 1.9 yes
As it is seen, the rows have a name. However I don't know how to access a
2009 Oct 26
1
GLMMPQL and negbinomial: trouble with the X-axis in PREDICT
I'm having some difficulty with graphing outputs of a GLM model I've
been working. I have count data for both my predictor (only 1) and
response variables, and I have pseudoreplication which I've modeled as
a random effect. The odTest() from pscl:: indicated that the negative
binomial distribution fit better than Poisson, and I then proceeded by
estimating theta from glm.nb.
My
2008 Oct 19
1
number of required trials
Dear Experts,
Probably trivial, but I am struggling to get what I want:
I need to know how the number of required trials to get a certain number of successes.
By example:
How many trials do I need to have 98% probability of 50 successes, when the a priory probability is 0.1 per trial.
The Negative binomial function may do the job (not sure):
NegBinomial {stats}
The Negative Binomial
2005 Jan 27
3
Domain admins not getting local admin rights
Hi there,
I switched servers yesterday.
The old server was running 2.2.7a-1 on RedHat 8.0.
The new server is 3.0.8-0.pre1.3 on Fedora Core 3.
I did the migration by copying the following:
/etc/passwd
/etc/group
/etc/shadow
/etc/samba/*
I then copied /home and fixed all the permissions on stuff.
I then started up samba on the new server, and unplugged the old one.
Most everything went
1997 Jul 09
1
R-beta: Problem with `rpois'
There is a problem with `rpois'. It does seem to take care about the
order of the arguments. This is an example:
> rpois(n=1,lambda=2)
[1] 3
> rpois(lambda=2,n=1)
[1] 2 0
It obviously uses the first argument as the number of samples to be
drawn, which is wrong.
I used Version 0.49 Beta (April 23, 1997).
Fredrik
1997 Jul 09
1
R-beta: Problem with `rpois'
There is a problem with `rpois'. It does seem to take care about the
order of the arguments. This is an example:
> rpois(n=1,lambda=2)
[1] 3
> rpois(lambda=2,n=1)
[1] 2 0
It obviously uses the first argument as the number of samples to be
drawn, which is wrong.
I used Version 0.49 Beta (April 23, 1997).
Fredrik
2007 Oct 23
1
How to avoid the NaN errors in dnbinom?
Hi, The code below is giving me this error message:
Error in while (err > eps) { : missing value where TRUE/FALSE needed
In addition: Warning messages:
1: In dnbinom(x, size, prob, log) : NaNs produced
2: In dnbinom(x, size, prob, log) : NaNs produced
I know from the help files that for dnbinom "Invalid size or prob will
result in return value NaN, with a warning", but I am not able
2009 Apr 13
1
dnbinom with a large size parameter (PR#13650)
Full_Name: Andrey Pavlov
Version: 2.7.1 (2008-06-23)
OS: Windows Vista
Submission from: (NULL) (67.193.233.43)
Dear developers,
I discovered an issue with the dnbinom function while fitting a negative
binomial model to my data. I was using the size and mu parameterization. When
the size gets large enough, the function begins to return 1, while it should
instead return the respective Poisson
2001 Dec 09
1
Help for Power analysis
Dear colleague,
I not sure this R code is correctly ? I would to show
the number of Sample Size at Sample Size Axis that line
draw from Power Axis (80%) from R code.
How I show this and select the most appropriate of
this power (.79955687 - 80983575).
Thank for your help and answer.
Best Regards,
Nikom Thanomsieng,
Email: nikom at kku.ac.th
....
#Power analysis: Sample size for
2005 Mar 03
1
Negative binomial regression for count data
Dear list,
I would like to fit a negative binomial regression model as described in "Byers AL, Allore H, Gill TM, Peduzzi PN., Application of negative binomial modeling for discrete outcomes: a case study in aging research. J Clin Epidemiol. 2003 Jun;56(6):559-64" to my data in which the response is count data. There are also 10 predictors that are count data, and I have also 3
2007 Feb 20
1
Simplification of Generalised Linear mixed effects models using glmmPQL
Dear R users I have built several glmm models using glmmPQL in the
following structure:
m1<-glmmPQL(dev~env*har*treat+dens, random = ~1|pop/rep, family =
Gamma)
(full script below, data attached)
I have tried all the methods I can find to obtain some sort of model fit
score or to compare between models using following the deletion of terms
(i.e. AIC, logLik, anova.lme(m1,m2)), but I
2008 Jul 04
1
update on dnbinom with large "size"
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~ turns out I don't need to look at the C code.
~ if one uses the mu/size parameterization of the
negative binomial, R computes size/(size+mu) to
switch parameterizations. If size>>mu this
gets rounded to 1 ... should be easy enough
to test and return NA under these circumstances?
function (x, size, prob, mu, log = FALSE)
{
~ if