Displaying 20 results from an estimated 1000 matches similar to: "syntax for pdDiag (nlme)"
2001 Dec 03
0
problems with nmle
Following the Indomethicin example in Pinheiro & Bates, chapter 6,
page 277 etc, coming to the following comand:
fm2Indom.nlme <- update( fm1Indom.nlme,
random = pdDiag(A1 + lrc1 + A2 ~ 1) )
debugging nlme gives the following output:
Browse[1]> n
debug: modelResid <- ~eval(model, data.frame(data, getParsNlme(plist,
fmap, rmapRel, bmap, groups, beta, bvec, b, level,
2007 Aug 23
0
Lost in substitute: nlsList and nlme with dynamic formula
DeaR
I am trying to use a dynamically create formula with nlsList and nlme, but I
cannot get the environment of the string-generated formal to work similarly
to the manually entered one.
Any idea?
Dieter
#-----
library(nlme)
# Pinheiro/Bates p 280
fm1Indom.lis = nlsList(conc~SSbiexp(time,A1,lrc1,A2,lrc2),
data=Indometh)
nlme(fm1Indom.lis,random=pdDiag(A1+lrc1+A2~1))
# works...
# Simulating
2006 Oct 09
1
split-plot analysis with lme()
Dear R-help,
Why can't lme cope with an incomplete whole plot when analysing a split-plot
experiment? For example:
R : Copyright 2006, The R Foundation for Statistical Computing
Version 2.3.1 (2006-06-01)
> library(nlme)
> attach(Oats)
> nitro <- ordered(nitro)
> fit <- lme(yield ~ Variety*nitro, random=~1|Block/Variety)
> anova(fit)
numDF denDF F-value
2003 May 23
2
predict.smooth.spline
I'm using R 1.7.0 on linux. With this version of R the package modreg is
automatically loaded at start of session. However attempting to use
predict.smooth.spline() produces Error: couldn't find function
predict.smooth.spline.
The function smooth.spline() is OK. What am I missing?
======================================
I.White
ICAPB, University of Edinburgh
Ashworth Laboratories, West
2005 Feb 10
1
Failure of update.packages()
Can anyone explain why with latest version of R (2.0.1) on FC3, installed
from R-2.0.1-0.fdr.2.fc3.i386.rpm, update.packages() produces the message
/usr/lib/R/bin/Rcmd exec: INSTALL: not found.
Indeed /usr/lib/R/bin seems to lack various shell scripts (INSTALL,
REMOVE, etc).
======================================
I.White
University of Edinburgh
Ashworth Laboratories, West Mains Road
Edinburgh
2004 Oct 27
1
se.contrast
After a one-way anova, se.contrast computes the standard error of a
contrast, but not the value of the contrast itself. Wouldn't this be
useful? Am I missing something?
======================================
I.White
ICAPB, University of Edinburgh
Ashworth Laboratories, West Mains Road
Edinburgh EH9 3JT
Fax: 0131 650 6564 Tel: 0131 650 5490
E-mail: iwhite at staffmail.ed.ac.uk
2006 Apr 06
1
polynomial predict with lme
Does lme prediction work correctly with poly() terms?
In the following simulated example, the predictions
are wildly off.
Or am I doing something daft?
Milk yield for five cows is measured weekly for 45 weeks.
Yield is simulated as cubic function of weekno + random
cow effect (on intercept) + residual error.
I want to recover an estimate of the fixed curve.
###############
library(nlme)
2003 May 08
2
natural splines
Apologies if this is this too obscure for R-help.
In package splines, ns(x,,knots,intercept=TRUE) produces an n by K+2
matrix N, the values of K+2 basis functions for the natural splines with K
(internal) knots, evaluated at x. It does this by first generating an
n by K+4 matrix B of unconstrained splines, then postmultiplying B by
H, a K+4 by K+2 representation of the nullspace of C (2 by K+4),
2003 Sep 07
3
bug in crossprod? (PR#4092)
# Your mailer is set to "none" (default on Windows),
# hence we cannot send the bug report directly from R.
# Please copy the bug report (after finishing it) to
# your favorite email program and send it to
#
# r-bugs@r-project.org
#
######################################################
# The last line of following code produces a segmentation fault:
x <- 1:10
f <- gl(5,2)
2002 Aug 22
1
aov bug? (PR#1930)
R : Copyright 2001, The R Development Core Team
Version 1.4.0 (2001-12-19)
R is free software and comes with ABSOLUTELY NO WARRANTY.
You are welcome to redistribute it under certain conditions.
Type `license()' or `licence()' for distribution details.
R is a collaborative project with many contributors.
Type `contributors()' for more information.
Type `demo()' for some demos,
1999 Sep 03
1
pictex device driver
I can't get LaTeX to recognize the output from the pictex device
driver. Are these commands for some special latex package which I
don't know about?
************************************************
* I.White *
* ICAPB, University of Edinburgh *
* Ashworth Laboratories, West Mains Road *
* Edinburgh EH9 3JT
2007 May 11
3
A simple question regarding plot of nls objects
Hi,
I was trying to run the example of Indomethacin kinetics from the book:
## From Pinheiro/Bates, Mixed-Effects-Models in S and S-Plus,
## Springer, Second Printing 2001, Section 6.2
library(nlme)
plot(Indometh)
fm1Indom.nls <- nls(conc~SSbiexp(time,A1,lrc1,A2,lrc2), data=Indometh)
summary(fm1Indom.nls)
plot(fm1Indom.nls,Subject~resid(.),abline=0)
## ....
the last plot command gives me the
2006 Jul 08
1
denominator degrees of freedom and F-values in nlme
Hello,
I am struggling to understand how denominator degrees of freedom and
subsequent significance testing based upon them works in nlme models.
I have a data set of 736 measurements (weight), taken within 3
different age groups, on 497 individuals who fall into two
morphological catagories (horn types).
My model is: Y ~ weight + horn type / age group, random=~1|individual
I am modeling
2000 Sep 04
2
bug in spline()? (PR#653)
BUG IN SPLINE()?
Version R-1.0.1, system i486,linux
If the spline(x,y,method="natural") function is given values outside the
range of the data, it does not give a warning. Moreover, the extrapolated
value reported is not the ordinate of the natural spline defined by (x,y).
Example. Let x <- c(2,5,8,10) and y <- c(1.2266,-1.7606,-0.5051,1.0390).
Then interpolate/extrapolate with
2013 Apr 23
2
SSbiexp
Hello all!
I have a problem to use a biexponential regression model:
I use this code:
n3<-nls(proc~SSbiexp(cls,a,b,c,d),data=bline) and this is the error message:
Error in nls(y ~ cbind(exp(-exp(lrc1) * x), exp(-exp(lrc2) * x)), data =
xy, :
singular gradient
My data is like this:
structure(list(proc = c(387.177462830167, 508.090511433077,
321.836817656365,
151.226805860727,
2005 Oct 10
4
plot - no main title and missing abscissa value
Hi all.
I have defined a plot thus:
par(mar=c(5,5,4,5),las=1, xpd=NA)
plot(Day, Ym1Imp, ylim=c(0,100), type="b", bty="l", main="Ym1
Expression", cex=1.3, xaxt="n", yaxt="n") #plot implant data
axis(side=1, at=c(0,1,3,5,7,10,14,21), labels=c(0,1,3,5,7,10,14,21)) #
label x axis
mtext("Day", side =1, at=10, line=3, cex=1.2) # title x
2007 May 21
2
comparing fit of cubic spline
I want to compare the fit of a quadratic model to continuous data, with that
of a cubic spline fit. Is there a way of computing AIC from for e.g. a GAM
with a smoothing spine, and comparing this to AIC from a quadratic model?
Cheers
******************************************
Tom Reed
PhD Student
Institute of Evolutionary Biology
102 Ashworth Laboratories
Kings Buildings
University of
2006 Oct 27
1
(no subject)
Hi,
I have generated a profile likelihood for a parameter (x) and am
trying to get 95% confidence limits by calculating the two points
where the log likelihood (LogL) is 2 units less than the maximum
LogL. I would like to do this by linear interpolation and so I have
been trying to use the function approxfun which allows me to get a
function to calculate LogL for any value of x within
2010 Jan 04
2
Piecewise regression in lmer
Dear all,
I'm attempting to use a piecewise regression to model the trajectory
of reproductive traits with age in a longitudinal data set using a
mixed model framework. The aim is to find three slopes and two points-
the slope from low performance in early age to a point of high
performance in middle age, the slope (may be 0) of the plateau from
the start of high performance to the
2001 Apr 25
1
manova
I'm running R 1.2.2. The help information for manova says that the
result is "A list with components
SS: A names list of sums of squares and product matrices.
Eigenvalues: A matrix of eigenvalues,
stats: A matrix of the statistics, approximate F value and degrees
of freedom."
However, when I run the example, with
fit <- manova(Y ~ rate*additive),
I find that fit$SS is NULL.