similar to: Problems and bugs in vgam()

Displaying 20 results from an estimated 110 matches similar to: "Problems and bugs in vgam()"

2007 Oct 29
1
VGAM and vglm
Hi Folks, I wonderif someone who is familiar with the details of vglm in the VGAM package can assist me. I'm new to using it, and there doesn;t seem much in the documentation that's relevant to the question below. Say I have a vector x of 0/1 responses and another vector y of 0/1 responses, these in fact being a bivariate set of 0/1 responses equivalent to cbind(x,y). E.g.
2009 Aug 21
2
using loglog link in VGAM or creating loglog link for GLM
I am trying to figure out how to apply a loglog link to a binomial model (dichotomous response variable with far more zeros than ones). I am aware that there are several relevant posts on this list, but I am afraid I need a little more help. The two suggested approaches seem to be: 1) modify the make.link function in GLM, or 2) use the loglog or cloglog functions in the VGAM package.
2011 Sep 02
2
How to keep the same class?
Hello Please see the example below > class(testX) [1] "matrix" > class(testX[1,]) [1] "numeric" Why not matrix? What am I missing here? Is there a way to keep the same class? The reason for the question is that I want to implement a k-step ahead prediction for my own routines and R wrecks does not seem to like [1,] as shown below. >
2006 Oct 27
0
VGAM package released on CRAN
Dear useRs, upon request, the VGAM package (currently version 0.7-1) has been officially released on CRAN (the package has been at my website http://www.stat.auckland.ac.nz/~yee/VGAM for a number of years now). VGAM implements a general framework for several classes of regression models using iteratively reweighted least squares (IRLS). The key ideas are Fisher scoring, generalized linear and
2010 Sep 10
1
lme, groupedData, random intercept and slope
Windows Vista R 2.10.1 Does the following use of groupedData and lme produce an analysis with both random intercept and slope, or only random slope? zz<-groupedData(y~time | Subject,data=data.frame(data), labels = list( x = "Time", y = "y" ), units = list( x = "(yr)", y = "(mm)") ) plot(zz)
2005 May 28
3
Incompatibility with VGAM
I just discovered that when the VGAM package (not on CRAN) is loaded, glm() doesn't work. This is because VGAM defines a family function() which gets found by glm() in place of the family function from stats. Then VGAM:::family returns an object which doesn't have a $family component, (it has a component $vfamily). I thought namespaces should protect us from this happening? Kjetil --
2012 Jun 05
1
Do YOU know an equation for splines (ns)?
Hi, I am looking at the change in N concentration in plant roots over 4 time points and I have fit a spline to the data using ns and lme: fit10 <- lme( N~ns(day, 3), data = rcn10G) I may want to adjust the model a little bit, but for now, let's assume it's good. I get output for the fixed effects: Fixed: N ~ ns(day, 3) (Intercept) ns(day, 3)1 ns(day, 3)2 ns(day, 3)3
2012 May 31
0
splines and ns equation
Hi, I am looking at the change in N concentration in plant roots over 4 time points and I have fit a spline to the data using ns and lme: fit10 <- lme( N~ns(day, 3), data = rcn10G) I may want to adjust the model a little bit, but for now, let's assume it's good. I get output for the fixed effects: Fixed: N ~ ns(day, 3) (Intercept) ns(day, 3)1 ns(day, 3)2 ns(day, 3)3 1.15676524
2004 Jul 12
6
proportions confidence intervals
Dear R users this may be a simple question - but i would appreciate any thoughts does anyone know how you would get one lower and one upper confidence interval for a set of data that consists of proportions. i.e. taking a usual confidence interval for normal data would result in the lower confidence interval being negative - which is not possible given the data (which is constrained between
2009 Mar 26
0
VGAM and cnstraints
Dear R-Users, I am learning how to use the package VGAM to do multinomial regressions. I have worked through the example provided by UCLA stats group: http://www.ats.ucla.edu/stat/r/dae/mlogit.htm However - what I would like to learn is how to use the constraint option. So in the example given in the link i would like to introduce a constraint that does not allow individuals of age less than
2008 Feb 08
0
Cumulative multinomial regression using VGAM
Hi, I am trying to carry out a multinomial regression using the cumlogit link function. I have tried using the VGAM package, and have gotten some results... fit1 <- vgam(Y ~ X1 + X2 + X3 + X4, cumulative(link=logit,intercept.apply=FALSE,parallel=TRUE), data = data1 ) The problem arrises when I try to get the information out of the fitted object. I can
2009 Jan 29
0
Problem VGAM and Predict
Hello, since I installed the package VGAM I have problems useing the predict for othere methods. for example I have a model from glm and polr the command predict(model) I get the error: unable to find an inherited method for function "predict", for signature "polr". Has perhaps anybody a solution, because Iwould need vglm and also other methods like tree in a loop. Thanks a
2007 May 31
0
VGAM package
Hi, R-users Could someone help me to understand this following error. I'm using vglm function in VGAM package Best regards and thank you for your ehlp ######## mydata <- read.table("Data2_overruns.csv", sep =";", header = T, row.names=NULL) > attach(mydata) > > y <- mydata$cat.event > phase.vol <-mydata$phase.vol > pilote <- mydata$pilote
2005 Jun 06
0
VGAM weights
sorry...its the same post but this time with subject dear all: I want try the vgam function in VGAM library, but I'm stucked since I can't define the weights. This is because I dont understand well the concept of "matrix-band" (even after read the reference card). I was wondering if someone have some tutorial examples of how to define weights on a matrix form, in VGAM. thank
2010 Jul 05
1
question concerning VGAM
Hello everyone, using the VGAM package and the following code library(VGAM) bp1 <- vglm(cbind(daten$anzahl_b, daten$deckung_b) ~ ., binom2.rho, data=daten1) summary(bp1) coef(bp1, matrix=TRUE) produced this error message: error in object$coefficients : $ operator not defined for this S4 class I am bit confused because some day ago this error message did not show up and
2005 Apr 10
2
residuals in VGAM
Hi all: I want to fit a multinomial logit model with VGAM package, however I cannot find a way to check the residuals since residuals(my_model) and resid(my_model) does not work. Any suggestions? Thanks in advance. Alex Brito [[alternative HTML version deleted]]
2006 Oct 05
2
VGAM Package ?
Hi! R users I would like to ask you where could we find the VGAM Package. I don't find it in the list of packages. Thak you for your help Lassana KOITA Etudes de S?curit? et d'Exploitation a?roportuaires / Safety Study & Statistical analysis Service Technique de l'Aviation Civile (STAC) / Civil Aviation Technical Department Direction G?n?rale de l'Aviation Civile (DGAC) /
2007 Jun 13
1
VGAM Pareto
I would like to fit a Pareto Distribution and I am using the following codes fit=vglm(ycf1 ~ 1, pareto1(location=alpha), trace=TRUE, crit="c") fitted(fit) But the fitted values turn out to be the same for each observation. I guess the problem is with "ycf1 ~ 1", I would be grateful if anyone can give me some advice on how to define the formula. Many thanks -- View this
2008 Nov 14
0
VGAM package released on CRAN
Dear Prof. Thomas Yee I$B!G(Bm very interested in your R program VGAM. I tried below your data: # Nonparametric proportional odds model data(pneumo)pneumo = transform(pneumo, let=log(exposure.time))vgam(cbind(normal,mild,severe) ~ s(let), cumulative(par=TRUE), pneumo) However, the results by Version of VGAM are different; ----------The result by Version 0.7-7
2009 Mar 26
0
(Interpretation) VGAM - FRECHET 3 parameters by maximum likelihood estimation for
Dear R Helpers This is the R code (which I have slightly changed) I got in VGAM package for estimating the parameters of FRECHET. _________________________________________________________________ y = rfrechet(n <- 100, shape=exp(exp(0))) # (A) fit3 = vglm(y ~ 1, frechet3(ilocation=0), trace=TRUE, maxit=155) # (B) coef(fit3, matrix=TRUE) # (C)