Displaying 20 results from an estimated 3000 matches similar to: "system is exactly singular"
2003 Sep 03
1
glmmPQL probelm
Dear listers,
First let me appologize if the same mail arrives multiple times. Recently I
had some probelms sending my e-mails to the list.
I encountered a problem when running glmmPQL procuedure doing multilevel
modeling with a dichotomous outcome.
Those are the two error messages I usually get:
Error in logLik.reStruct(object, conLin) :
NA/NaN/Inf in foreign function call (arg 3)
2006 Jan 10
1
glmmPQL / "system is computationally singular"
Hi,
I'm having trouble with glmmPQL from the MASS package.
I'm trying to fit a model with a binary response variable, two fixed
and two random variables (nested), with a sample of about 200,000
data points.
Unfortunately, I'm getting an error message that is difficult to
understand without knowing the internals of the glmmPQL function.
> model <- glmmPQL(primed ~
2012 Feb 28
1
Error in solve.default(res$hessian * n.used) :Lapack routine dgesv: system is exactly singular
Hi there!
I´m a noob when it comes to R and I´m using it to run statisc analysis.
With the code for ARIMA below I´m getting this error: Error in
solve.default(res$hessian * n.used) :Lapack routine dgesv: system is
exactly singular
The code is:
> s.ts <- ts(x[,7], start = 2004, fre=12)
> get.best.arima <- function (x.ts, maxord=c(1,1,1,1,1,1))
+ {
+ best.aic <- 1e8
+ n <-
2006 Mar 31
1
model comparison with mixed effects glm
I use model comparison with glms without mixed effects with
anova(modelA,modelB),
with mixed effects glm (glmmPQL), this doesn't work. Is there a way to
compare model fits with glmmPQL's?
Paula M. den Hartog
Behavioural Biology
Institute of Biology Leiden
Leiden University
[[alternative HTML version deleted]]
2012 Jan 10
1
Lapack routine dgesv: system is exactly singular
Hi
I have a problem with this error, I have searched the archives and found
previous discussion about this, can I cannot understand how the explanations
apply to what I am trying to do.
I am trying to do Log_rank Survival analysis, I have included tables and str
command, is it a factor/integer problem? If so how do I correct this, as all
my attempt to recode the data have failed.
>
2005 Aug 20
1
glmmPQL and Convergence
I fit the following model using glmmPQL from MASS:
fit.glmmPQL <-
glmmPQL(ifelse(class=="Disease",1,0)~age+x1+x2,random=~1|subject,family=binomial)
summary(fit.glmmPQL)
The response is paired (pairing denoted by subject), although some
subjects only have one response. Also, there is a perfect positive
correlation between the paired responses. x1 and x2 can and do differ
within each
2004 Oct 28
0
sem : Error in solve.default(C[ind, ind]) : Lapack routine dgesv: system is exactly singular
Hi R-users:
When I run the R script (as the following), I got the error message:
Error in solve.default(C[ind, ind]) : Lapack routine dgesv: system is
exactly singular.
Any help is appreciated.
Ying
library(sem)
R.pw <- matrix(c(
1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0.2137356, 0.2137356, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
2009 Apr 15
2
AICs from lmer different with summary and anova
Dear R Helpers,
I have noticed that when I use lmer to analyse data, the summary function
gives different values for the AIC, BIC and log-likelihood compared with the
anova function.
Here is a sample program
#make some data
set.seed(1);
datx=data.frame(array(runif(720),c(240,3),dimnames=list(NULL,c('x1','x2','y'
))))
id=rep(1:120,2); datx=cbind(id,datx)
#give x1 a
2006 Feb 27
2
singular convergence in glmmPQL
I am using the 'glmmPQL function in the 'MASS' library to fit a mixed effects logistic regression model to simulated data. I am conducting a series of simulations, and with certain simulated datasets, estimation of the random effects logistic regression model unexpectedly terminates. I receive the following error message from R:
Error in lme.formula(fixed=zz + arm.long,random=~1 |
2011 Oct 06
1
anova.rq {quantreg) - Why do different level of nesting changes the P values?!
Hello dear R help members.
I am trying to understand the anova.rq, and I am finding something which I
can not explain (is it a bug?!):
The example is for when we have 3 nested models. I run the anova once on
the two models, and again on the three models. I expect that the p.value
for the comparison of model 1 and model 2 would remain the same, whether or
not I add a third model to be compared
2019 Apr 24
1
Bug in "stats4" package - "confint" method
Dear R developers,
I noticed a bug in the stats4 package, specifically in the confint method applied to ?mle? objects.
In particular, when some ?fixed? parameters define the log likelihood, these parameters are stored within the mle object but they are not used by the ?confint" method, which retrieves their value from the global environment (whenever they still exist).
Sample code:
>
2009 Apr 20
0
system is exactly singular
Hi. I have a csv file. I imported it with
mydata<-read.table("C:/dataForR/radiology/WordFrequency.csv", header=TRUE,
sep=",")
> dim(mydata)
[1] 982 925
The first column had the doc numbers like doc1, doc2, etc. so I did
mydataNum<-mydata[,-1]
> dim(mydataNum)
[1] 982 924
The second to last column was also not numeric and so I did
>
2018 Jan 17
1
Assessing calibration of Cox model with time-dependent coefficients
I am trying to find methods for testing and visualizing calibration to Cox
models with time-depended coefficients. I have read this nice article
<http://journals.sagepub.com/doi/10.1177/0962280213497434>. In this paper,
we can fit three models:
fit0 <- coxph(Surv(futime, status) ~ x1 + x2 + x3, data = data0) p <-
log(predict(fit0, newdata = data1, type = "expected")) lp
2015 Mar 25
4
F77_CALL/NAME problem
Dear R-devel,
I am trying to use Fortran DGESV subroutine into C. Here it is the relevant
part of the C file I am currently writing
#include<stdio.h>
#include<R.h>
#include<Rmath.h>
#include<math.h>
void F77_NAME(DGESV)( int*, int*, double*, int*, int*, double*, int*, int*);
void solve( int *p, double *A, double *Ainv)
{
...
F77_CALL(DGESV)(p, p, Ain, p, ipiv,
2009 Sep 22
1
Singular model.matrix of nested designs
Hi,
I want to do ANOVA for nested designs like following. I don't
understand why the matrix (t(X) %*% X) is singular. Can somebody help
me understand it?
Regards,
Peng
> a=2
> b=3
> n=4
> A = as.vector(sapply(1:a,function(x){rep(x,b*n)}))
> B = as.vector(sapply(1:(a*b), function(x){rep(x,n)}))
> cbind(A,B)
A B
[1,] 1 1
[2,] 1 1
[3,] 1 1
[4,] 1 1
[5,] 1 2
[6,] 1 2
[7,]
2012 Nov 15
1
Step-wise method for large dimension
Hi ,
I want to apply the following code fo my data with 400 predictors.
I was wondering if there ia an alternative way instead of typing 400 predictors for the following code.
I really appreciate your help.
fit0<-lm(Y~1, data= mydata)
fit.final<- lm(Y~X1+X2+X3+.....+X400, data=mydata) ???
step(fit0, scope=list(lower=fit0, upper=fit.final), data=mydata, direction="forward")
2018 Jan 18
1
Time-dependent coefficients in a Cox model with categorical variants
First, as others have said please obey the mailing list rules and turn of
First, as others have said please obey the mailing list rules and turn off html, not everyone uses an html email client.
Here is your code, formatted and with line numbers added. I also fixed one error: "y" should be "status".
1. fit0 <- coxph(Surv(futime, status) ~ x1 + x2 + x3, data = data0)
2. p
2009 May 11
1
Warning trying to plot -log(log(survival))
windows xp
R 2.8.1
I am trying to plot the -log(log(survival)) to visually test the proportional hazards assumption of a Cox regression. The plot, which should give two lines (one for each treatment) gives only one line and a warning message. I would appreciate help getting two lines, and an explanation of the warning message. My problem may the that I have very few events in one of my strata,
2001 Sep 12
1
error in nlme
I'm getting an error from nlme that has me stymied. I have a data set
,'mydata', with variables: AChE, Dose, sex, set, and mrid; 'set' and 'mrid'
indicate two levels of nesting, with 'set' nested within 'mrid'. I want to
fit the model:
mod <- nlme(AChE ~ Cexp(Dose, A, B, m), data=mydata, fixed = A+B+M~sex,
random=A+B+m~sex | mrid/set,
2009 May 10
2
plot(survfit(fitCox)) graph shows one line - should show two
R 2.8.1
Windows XP
I am trying to plot the results of a coxph using plot(survfit()). The plot should, I believe, show two lines one for survival in each of two treatment (Drug) groups, however my plot shows only one line. What am I doing wrong?
My code is reproduced below, my figure is attached to this EMail message.
John
> #Create simple survival object
>