Displaying 20 results from an estimated 5000 matches similar to: "How to do poisson distribution test like this?"
2013 Feb 25
3
Empirical Bayes Estimator for Poisson-Gamma Parameters
Dear Sir/Madam,
I apologize for any cross-posting. I got a simple question, which I thought
the R list may help me to find an answer. Suppose we have Y_1, Y_2, ., Y_n ~
Poisson (Lambda_i) and Lambda_i ~Gamma(alpha_i, beta_i). Empirical Bayes
Estimator for hyper-parameters of the gamma distr, i.e. (alpha_t, beta_t)
are needed.
y=c(12,5,17,14)
n=4
What about a Hierarchal B ayes
2003 Jul 10
1
The question is on Symmetry model for square table.
Please help,
I tried a program on S-plus, and it worked. Also I tried the same
program on R but not worked. Here is the programme. I put it in a
function form. The model and assumption are at the bottom.
where
counts<-c(22,2,2,0,5,7,14,0,0,2,36,0,0,1,17,10)
which is name.data, i is row size and j is the column size.
symmetry
function(i, j, name.data)
{
row <- (c(1:i))
col <-
2018 Feb 03
2
find unique and summerize
Thank you so much Rui.
1. How do I export this table to excel file?
I used this
tbl1 <- table(Country, IDNum)
tbl2=addmargins(tbl1)
write.xlsx(tbl2,"tt1.xlsx"),sheetName="summary", row.names=FALSE)
The above did not give me that table.
2. I want select those unique Ids that do have records in all countries.
From the above data set, this ID
2011 Dec 30
2
Joint modelling of survival data
Assume that we collect below data : -
subjects = 20 males + 20 females, every single individual is independence,
and difference
events = 1, 2, 3... n
covariates = 4 blood types A, B, AB, O
http://r.789695.n4.nabble.com/file/n4245397/CodeCogsEqn.jpeg
?m = hazards rates for male
?n = hazards rates for female
Wm = Wn x ?, frailty for males, where ? is the edge ratio of male compare to
female
Wn =
2007 Sep 16
2
are hurdle logit-poisson model and posson model nested?
Dear Listers,
I have a general statistical question. Are hurdle logit-poisson model
and posson model nested?
Thank you so much?
2006 Apr 19
3
About poisson distribution fitting and testing
Hi All,
I have a sequence of positive integers, which is right skewed. The mean
value is 6 and variance is 11.
I suspect it can be fitted by poisson distribution. But I'm not familiar
with the function to fit distribution.
Could you please help me with it? Also, once I fit the poisson
distribution, how can I check the good-ness of this fitting?
Thank you!
[[alternative HTML
2005 May 01
2
simulate zero-truncated Poisson distribution
Dear All
I would like to know whether it is possible with R to
generate random numbers from zero-truncated Poisson
distribution.
Thanks in advance,
Galina
2010 Nov 03
2
multivariate Poisson distribution
Hello, from a search of the archives and functions, I am looking for information on creating random correlated counts from a multivariate Poisson distribution. I can not seem to find a function that does this. Perhaps, it has not yet been created. Has anyone created an R package that does this.
thanks,
Jourdan Gold
[[alternative HTML version deleted]]
2018 Feb 03
2
find unique and summerize
Hi all,
I have a data set need to be summarized by unique ID (count and sum of a
variable)
A unique individual ID (country name Abbreviation followed by an integer
numbers) may have observation in several countries. Then the ID was
changed by adding the country code as a prefix and new ID was constructed
or recorded like (country code, + the original unique ID Example
original ID
2012 May 31
1
svychisq??
Hello forum,
I
want to do a test of independence
with svychisq, but I
get an error, then this my code:
am18 <- read.spss("C:/Users/diana/Dropbox/Semestre
10/Tesis 10/Tesis Diana/AMcomuna18-29MAR2012.sav",
use.value.labels=TRUE, max.value.labels=Inf,
to.data.frame=TRUE)
b<-matrix(c(am18$N6_MANZANA),ncol=1)
c<-matrix(c(am18$PM1_1_PONDEMUESTRA),ncol=1)
2009 Jan 20
1
Poisson GLM
This is a basics beginner question.
I attempted fitting a a Poisson GLM to data that is non-integer ( I believe
Poisson is suitable in this case, because it is modelling counts of
infections, but the data collected are all non-negative numbers with 2
decimal places).
My question is, since R doesn't return an error with this glm fitting, is it
important that the data is non-integer. How does
2008 Jan 25
1
Poisson Maximum Likelihood Estimation
Hi
I am trying to carry out some maximum likelihood estimation and I'm not
making much headway, and I'm hoping that someone will be able to point me in
the right direction.
I am modelling mortality statistics. One way to do this is to model the
mortality rate (or, more accurately, log of the mortality rate, log_m) as
(say) a constant plus a proportion of age, plus time, so:
r_1 <-
2012 Oct 14
2
Poisson Regression: questions about tests of assumptions
I would like to test in R what regression fits my data best. My dependent
variable is a count, and has a lot of zeros.
And I would need some help to determine what model and family to use
(poisson or quasipoisson, or zero-inflated poisson regression), and how to
test the assumptions.
1) Poisson Regression: as far as I understand, the strong assumption is
that dependent variable mean = variance.
2010 Sep 12
1
R-equivalent Stata command: poisson or quasipoisson?
Hello R-help,
According to a research article that covers the topic I'm analyzing,
in Stata, a Poisson pseudo-maximum-likelihood (PPML) estimation can be
obtained with the command
poisson depvar_ij ln(indepvar1_ij) ln(indepvar2_ij) ...
ln(indepvarN_ij), robust
I looked up Stata help for the command, to understand syntax and such:
www.stata.com/help.cgi?poisson
Which simply says
2008 Nov 14
2
GAM and Poisson distribution
Hi -I'm running a GAM with 7 explanatory variables with a Poisson error
structure. All of the variables are continuous so I'm getting error
messages in R.
cod.fall.full.gam.model<-gam(Kept.CPUE~s(HOUR)+s(LAT_dec)+s(LONG_dec)+s(meantemp_C)+s(meandepth_fa)+s(change_depth)+s(seds),
data=cod.fall.version2,family=poisson)
In dpois(y, mu, log = TRUE) ... : non-integer x = 5.325517
2009 Mar 24
3
generalized Poisson regression
Dear sir,
I want to know about R command for parameter estimation for generalized
Poisson regression.
yours faithfully
Arafat Ud Zaman
4th year(Hons)
Applied statistics
University of Dhaka
Mob- +8801715173176
E-mail: arafat.zaman@yahoo.com
azaman1@isrt.ac.bd
azaman1@quantummethod.org.bd
[[alternative HTML version deleted]]
2012 Jul 06
4
Poisson Ridge Regression
Dear everyone
I'm dealing with a problem related to Poisson Ridge Regression. If
anyone can help me in this regard by telling if any changes in the
source code of "glm.fit" may help
--
Regards
Umesh Khatri
2006 Jan 18
4
negative predicted values in poisson glm
Dear R helpers,
running the following code of a glm model of the family poisson, gives
predicted values < 0. Why?
library(MASS)
library(stats)
library(mvtnorm)
library(pscl)
data(bioChemists)
poisson_glm <- glm(art ~ fem + mar + kid5 + phd + ment, data = bioChemists,
family = poisson)
predicted.values = predict(poisson_glm)
range(predicted.values)
Thank you in advance for any hints.
2006 Feb 06
3
power and sample size for a GLM with poisson response variable
Hi all,
I would like to estimate power and necessary sample size for a GLM with
a response variable that has a poisson distribution. Do you have any
suggestions for how I can do this in R? Thank you for your help.
Sincerely,
Craig
--
Craig A. Faulhaber
Department of Forest, Range, and Wildlife Sciences
Utah State University
5230 Old Main Hill
Logan, UT 84322
(435)797-3892
2009 Feb 02
2
logLik for poisson models
Dear all,
I have a very basic question:
how does the logLik function work for poisson models?
Example:
I simulate 20 observations from a Poisson distribution with mean 800.
y <- rpois(20,800)
model <- glm(y ~ 1, family=poisson())
logLik(model)
I would like to know what's the exact formula the function logLik uses.
I looked at ?extractAIC but I cannot sort it out.
Can you please