similar to: Zero-inflated neg.bin. model and pscl package

Displaying 20 results from an estimated 500 matches similar to: "Zero-inflated neg.bin. model and pscl package"

2006 Aug 30
1
Optimization
Dear R-list, I'm trying to estimate the relative importance of 6 environmental variables in determining clam yield. To estimate clam yield a previous work used the function Yield = (A^a*B^b*C^c...)^1/(a+b+c+...) where A,B,C... are the values of the environmental variables and the weights a,b,c... have not been calibrated on data but taken from literature. Now I'd like to estimate the
2010 Feb 09
2
Comparing means and trends in short time-series
Dear R-list, I have a statistical problem with the comparison of short time-series, representing densities of fish in different streams. For each stream (6 in total, here below showed only part of the dataset) I have 8 years of density data, as follows: year density stream 1 2000 0.51 stream1 2 2001 0.87 stream1 3 2002 0.68 stream1 4 2003 0.56 stream1 5 2004 0.50 stream1 6
2006 Aug 04
3
Help with short time series
Dear R-list, I have a statistical problem with the comparison of two short time-series of density data in an ecological framework. I have to compare two short time series (5 years, one value for each year) of species density data (it is the density of fish in two different streams) to test if the two means of the five densities are significantly different, so basically if the two mean
2009 Jan 13
5
Trouble about the interpretation of intercept in lm models
Hallo, yesterday I was puzzled when I discovered that I probabliy miss something in the interepretation of intercept in two-way lm models. I thought that the intercept, using the default contr.treatment contrasts, represents the mean of the group of observations having zero in all column of the model.matrix. It turns out not to be case To be more more clear I am attaching a short example:
2004 Jul 23
1
difference between nls and nlme approaches
Hallo, I have a question that is more statistic related than about nlme and R functioning. I want to fit a complicated nonlinear model with nlme with several different measures of transpiration taken on each of the 220 trees grouped in 8 families. The unknown parameters of the model are three + their variances (and covariances). I want to estimate the variances among families of the
2012 Sep 10
1
Zero inflated Models- pscl package
Dear R users, I want to apply zero inflated models with continuous and categorical variables and I used pscl package from R and the zeroinf() function. My question are the follow: a) The value of fitted.values is mu or (1-p)*mu? where p is the probability of zero came form a zero point mass b) If mu is zero, how do i know if it is a zero from the zero point mass or from the count process?
2011 Mar 04
1
AIC on GLMM pscl package
Hello, I'm using GLMM on the pscl package and i'm not getting the AIC on the summary. The code i'm using is (example) : mmall3 <-glmmPQL(allclues ~ cycloc + male, data=dados, family=poisson, random=~1|animal/idfid) and the results: Linear mixed-effects model fit by maximum likelihood Data: dados AIC BIC logLik NA NA NA Random effects: Formula: ~1 | animal
2012 Oct 12
1
R not finding function in installed pscl package
Hi, This may be such a general question that my searches are just failing. I installed the pscl lib, all appears fine, installed it several different ways to be sure, but I am getting: Error: could not find function "zeroinfl" I double checked my spelling of the function and that it had not been evolved out of the package. It is in the same location as the other libraries that are
2006 Jul 20
0
Convergence warnings from zeroinfl (package pscl)
Dear R-Helpers, Can anyone please help me to interpret warning messages from zeroinfl (package pscl) while fitting a zero inflated negative binomial model? The console reports convergence and the parameters seam reasonable, but these <<Warning messages: 1: algorithm did not converge in: glm.fit(X, Y, family = poisson()) 2: fitted rates numerically 0 occurred in: glm.fit(X, Y, family =
2008 Sep 19
0
problems with too many NA in the function ideal() from pscl package.
Hi all, I'm trying to run some monte carlo simulation for my roll call data using the ideal() function, which resides in the pscl package. However, I'm receiving an error message that I don't understand. Error in ideal(a, maxiter = 1000, thin = 10, burnin = 50, store.item = TRUE, : NA/NaN/Inf in foreign function call (arg 13) my code is simple the following: > m_a <-
2005 Feb 21
2
Multiple servers, restricting user commands and LDAP
I have a set-up of 3 servers at disparate geographical locations. Server 1 provides web services, and users should be able to use sftp only. Admins should be able to get shells. Server 2 provides CVS services, and users sh ould be able to use cvs only. Admins should be able to get shells. Server 3 provides shell services for all users. There appears to be no easy way of implementing this within
2008 Feb 18
1
fitted.values from zeroinfl (pscl package)
Hello all: I have a question regarding the fitted.values returned from the zeroinfl() function. The values seem to be nearly identical to those fitted.values returned by the ordinary glm(). Why is this, shouldn't they be more "zero-inflated"? I construct a zero-inflated series of counts, called Y, like so: b= as.vector(c(1.5, -2)) g= as.vector(c(-3, 1)) x <- runif(100) # x
2010 Feb 25
1
Zero inflation model - pscl package
I have some questions regarding Zero Inflation Poisson models. I am using count data to analyze abundance trends of salamanders. However, I have surveys which differ in the amount of effort (i.e. the number of people searching and amount of time - I am using a museum database so not all surveys were conducted by me). Therefore I need to account for the effort. If change the count (response
2012 Jan 17
2
pscl package and hurdle model marginal effects
This request is related to the following post from last year: https://stat.ethz.ch/pipermail/r-help/2011-June/279752.html After reading the thread, the idea is still not clear. I have fitted a model using HURDLE from the PSCL package. I am trying to get marginal effects / slopes by multiplying the coefficients by the mean of the marginal effects (I think this is right). To my understanding, this
2012 Apr 26
2
Lambert (1992) simulation
Hi, I am trying to replicate Lambert (1992)'s simulation with zero-inflated Poisson models. The citation is here: @article{lambert1992zero, Author = {Lambert, D.}, Journal = {Technometrics}, Pages = {1--14}, Publisher = {JSTOR}, Title = {Zero-inflated {P}oisson regression, with an application to defects in manufacturing}, Year = {1992}} Specifically I am trying to recreate Table 2. But my
2007 Jul 05
2
Is it a bug ?
[[diverted from R-bugs to R-help by the list maintainer]] Dear Friend and distinguished R gurus, first of all really thank you very much for the marvellous tool that is R. I am using R 2.5.0, windows XP - italian language. I was perfoming some calculation on fractional exponential and I found a strange behaviour. I do not know if it is really a bug, but I would expect a different answer from
2011 Nov 15
2
[LLVMdev] Pass options to the linker
Hi all, I'm trying to use the PPL (Parma Polyhedra Library, bugseng.com/products/ppl) in one of my LLVM passes getting the error: > Error opening > '/home/jorge/SvnReps/Systems/llvm/build/Debug+Asserts/lib/MyAnalysis.so': > /home/jorge/SvnReps/Systems/llvm/build/Debug+Asserts/lib/MyAnalysis.so: > undefined symbol: _ZNK23Parma_Polyhedra_Library13PIP_Tree_Node2OKEv >
2011 Nov 15
0
[LLVMdev] Pass options to the linker
Hi Jorge, > I'm trying to use the PPL (Parma Polyhedra Library, > bugseng.com/products/ppl) in one of my LLVM passes getting the error: > >> Error opening >> '/home/jorge/SvnReps/Systems/llvm/build/Debug+Asserts/lib/MyAnalysis.so': >> /home/jorge/SvnReps/Systems/llvm/build/Debug+Asserts/lib/MyAnalysis.so: >> undefined symbol:
2011 Nov 15
1
[LLVMdev] Pass options to the linker
On Tuesday, November 15, 2011 at 10:11:25 (+0100), Duncan Sands wrote: >> Hi Jorge, >> >> > I'm trying to use the PPL (Parma Polyhedra Library, >> > bugseng.com/products/ppl) in one of my LLVM passes getting the error: >> > >> >> Error opening >> >> '/home/jorge/SvnReps/Systems/llvm/build/Debug+Asserts/lib/MyAnalysis.so':
2004 Mar 30
0
koq.q ---- Kent O' Quigley R2
Dear R-users, I apply to your kind attention to know if someone have used the Splus software koq.q (Kent & O'Quigley's measure of dependence for censored data) in R and kindly can help me. I have tried several times to contact the authors Andrej Blejec (andrej.blejec at uni-lj.si) or Janez Stare (janez.stare at mf.uni-lj.si) but unfortunately no one answered me. Following