Displaying 20 results from an estimated 8000 matches similar to: "Modelling Question"
2003 Oct 29
2
Where is rmutil package?
Pursing my earlier question, when I tried loading Lindsey's gnlm, I got
a
message
Loading required package: rmutil
Warning message:
There is no package called 'rmutil' in: library(package, character.only
= TRUE, logical = TRUE, warn.conflicts = warn.conflicts,
According to the R documentation
http://finzi.psych.upenn.edu/R/doc/html/packages.html
rmutil is in the standard
2003 Sep 21
1
Zero inflated count models
Can someone show me how to specify zero inflated poisson and zero
inflated negative poisson models in R? I would like to replicate the
example given in Long (1997: Regression Models for Categorical and
Limited Dependent Variables) in Chapter 8.5 (pp. 242-247).
TIA
Dirk
*************************************************
Dr. Dirk Enzmann
Criminological Research Institute of Lower Saxony
2004 Feb 10
1
generate random sample from ZINB
I want to generate 1,000 random samples of sample size=1,000 from ZINB.
I know there is a rnegbin() to generate random samples from NB, and I know
I can use
the following process:
do i=1 to 1000
n=0
do i=1 to 1000
if runi(1)>0.1 then x(i) = 0; else
x(i)=rnegbin();
n=n+1;
if n>1000 then stop;
end;
output;
end;
Anybody can help me out with the R code?
Thanks very much ahead of time.
2004 Apr 07
1
ZIB models
I attempted to contact Drew Tyre, but the email I have for him is no
longer in service.
Hopefully someone can help.
I'm using obs.error in R to model turtle occupancy in wetlands.
I have 4 species and 20 possible patch and landscape variables, which
I've been testing in smaller groups.
> zib.out<-obs.error(y=painted,m=numvis,bp=zvars,pcovar=7)
I get the following error
2009 Apr 20
1
doing zero inflated glmm for count data with fmr
Hello R users,
Doing My PhD I collected count data which I believe is zero inflated. I have
run a statistical model with lmer and family=poisson and got
summary(model)@sigma=1 so I believe there is no overdispertion. I would
like to use the fmr function from the 'gnlm' library but I just cannot
figure out from the examples in the help page and some forums out there how
to convert the lmer
2015 Jul 26
1
Get term from document by position
> Can you file a bug with some example outputs that are unrelated to the search string?
Here is the example (see attachment).
This example does the following:
1)First, it indexes text from the "text.txt" file (see attachment) (actually, this is the text of the following book: "Abbas, Lichtman. Basic immunology").
2)Next, it searches for the "extracellular
2005 Jan 20
5
glm and percentage data with many zero values
Dear all,
I am interested in correctly testing effects of continuous environmental
variables and ordered factors on bacterial abundance. Bacterial
abundance is derived from counts and expressed as percentage. My problem
is that the abundance data contain many zero values:
Bacteria <-
2003 Jan 17
2
Negative Binomial modelling
I have some data which I am trying to fit with a negative binomial
distribution. I have found the glm.nb function from MASS.
I have reason to believe that the mean parameter mu depends on
certain factors, and that the shape parameter theta depends on
others.
If, say, the factors are P and Q, it might be that
mu ~ P:Q and theta ~ P
(where mu ~ P:Q means that mu is a function of the pair (P,Q))
2005 Jun 08
1
Fitting Theoretical Distributions to Daily Rainfall Data
Dear List Members,
I need a bit help about fitting some theoretical
distributions (such as geometric, exponential,
lognormal or weibull distribution) to the following
*dry spell*, *wet spell*, *cycles (Wet-Dry or
Dry-Wet)* from my meteorological (daily rainfall) data
http://www.angelfire.com/ab5/get5/R.rainfall.txt only
for rainy seasen (july - september) of 14 years only:
2001 Feb 07
5
zero inflated poisson and censored-continuous models
I wonder if there is a package that will estimate a Zero Inflated Poisson
Model (ZIP), and also if there is a package that will estimate what is
called the Tobit model: that is a combination of censored and observed
values in the same sample.
Georgina Bermann
Biostatistics
AstraZeneca R&D M?lndal
-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-
r-help mailing
2001 May 09
3
odesolve check fails
Hi,
I just installed the odesolve package and ran the check command on it. It
failed trying to execute
library(gnlm).
Sure enough, there is no gnlm library on my system and I could not find it
on the CRAN archive either. Am I missing anything obvious or is gnlm some
private library that somehow found its way into the example section of
odesolve?
Thanks in advance,
Andy
2003 Oct 29
1
One inflated Poisson or Negative Binomal regression
Hello
I am interested in Poisson or (ideally) Negative Binomial regression
with an inflated number of 1 responses
I have seen JK Lindsey's fmr function in the gnlm library, which fits
zero inflated Poisson (ZIP) or zero inflated negative binomial
regression, but the help file states that for ' Poisson or related
distributions the mixture involves the zero category'.
I had thought
2023 Jul 21
1
plotly question
As you apparently haven't received any responses yet, I'll try to
suggest something useful. However, I have absolutely zero experience
with plotly, so this is just from general principles and reading the
plot_ly Help file, which says for the "..." arguments:
"Arguments (i.e., attributes) passed along to the trace type. See
schema() for a list of acceptable attributes for a
2023 Jul 21
2
plotly question
plotly is _not_ associated with posit. I think you are unlikely to find expertise with plotly in their forums. You might find help at stackoverflow.com.
On July 21, 2023 1:40:49 PM PDT, Bert Gunter <bgunter.4567 at gmail.com> wrote:
>As you apparently haven't received any responses yet, I'll try to
>suggest something useful. However, I have absolutely zero experience
>with
2005 Jul 20
4
poisson fit for histogram
I haven't been an R lister for a bit, but I hope to enlist someone's
help here. I think this is a simple question, so I hope the answer
is not much trouble. Can you please respond directly to this email
address in addition to the list (if responding to the list is
warranted)?
I have a histogram and I want to see if the data fit a Poisson
distribution. How do I do this? It is
2003 Jan 11
2
beta-binomial
Does anyone have R functions or library to fit a beta-binomial distribution
with glm? Thanks.
2003 Feb 19
2
GLM for Beta distribution
Hi R-help,
Is there such a thing as a function in R for fitting a GLM where the
response is distributed as a Beta distribution?
In my case, the response variable is a percentage ([0,1] and continuous).
The current glm() function in R doesn't include the Beta distribution.
Thank you for any help on this topic.
Sincerely,
Sharon K?hlmann
2000 Oct 27
1
- Estimate LD50 with bnlr{gnlm}
Hi,
I'm not yet familar with GLM and still learning.
How can I perform a BNL (to estimate LDp values) with matrixes like this
(N indicates the observed objects):
data from:
Kerr D, Meador J. 1996. "Modeling Dose Response Using Generalized Linear
Models". Environ Toxicol Chem 15(3)
conc respond n
0 0 20
0 1 19
0 1 20
0 0 20
13.5 5 23
13.5 2 20
29 9 20
29 6 20
53 12 20
53 15 20
85
2004 Jan 15
3
how to overlap plots
Dear R experts:
Can you help me to overlap a histogram and theoretical density curve of poison
distribution? for example data like this:
The numbers of sanils found in each of 100 sampling quadrats in an area were
as follows:
number of snails, r 0 1 2 3 4 5 8 15
f=frequency of r 69 18 7 2 1 1 1 1
apparently this is not Poison but near to Poison, How to overlap the
theoretical desity curve to
2002 Sep 27
3
Retaining regularly used add-ons
Hi everyone,
How might I go about configuring R to keep
add-on packages loaded from session to session?
Is this undesireable for some reason?
At present, I keep a file called "pckgs.txt" in my
working directory with, e.g.,
library(gnlm)
library(Hmisc)
...
and then type source("add-ons.txt") every time I start
a new session. I suspect there's a more elegant way
to hold