Displaying 20 results from an estimated 6000 matches similar to: "?glmm with correlation structure?"
2008 Aug 12
1
tilde on a spanish keyboard?
I was trying to help someone who used a spanish keyboard on a PC  
running Windows. he discovered that he had no tilde key. Does anyone  
know of any simple work-arounds?
Thanks,
Hank
Dr. Hank Stevens, Associate Professor
338 Pearson Hall
Botany Department
Miami University
Oxford, OH 45056
Office: (513) 529-4206
Lab: (513) 529-4262
FAX: (513) 529-4243
http://www.cas.muohio.edu/~stevenmh/
2005 Oct 26
2
changing memory limits to speed up lsoda
Hi All,
I am running R 2.2.0 on Mac OS 10.4.2, dual G5 processors with 8 Gig  
RAM.
I am running a simulation with lsoda that requires ~378 s to complete  
one set of time intervals. I need to optimize the parameters, and so  
need to considerably speed up the simulation.
I have tried to figure out how to change the appropriate memory  
allocation and have search R help and Introductory
2007 Jun 11
1
Package update announcements
Hi Folks,
I was wondering what everyone thought about adding a sentence to each  
package update announcement that described what the package did. R  
extensions are so numerous that it is difficult to keep up with them.  
Would it be appropriate to ask package developers to add a brief  
sentence about what the package does, when they announce updates?
I would benefit from such descriptions.
2003 Nov 17
2
Symbolic math?
Hi Folks,
I am using Windows 2000 and was wondering what (Open Source) software R 
users use or might recommend for symbolic computations (aside from the ol' 
noggin, e.g., Maxima, Mathomatic) .
Thanks,
Hank
Dr. Martin Henry H. Stevens, Assistant Professor
338 Pearson Hall
Botany Department
Miami University
Oxford, OH 45056
Office: (513) 529-4206
Lab: (513) 529-4262
FAX: (513) 529-4243
2003 Apr 29
1
plot with nlme
Using R v. 1.7.0 on Windows 2000
I would like to plot the fitted values of a model as a function of a 
continuous covariate, augmented with data (e.g., augPred) grouping by 
combinations of fixed effects. I have not been able to use augPred 
effectively, and am wondering if it does not handle unbalanced data (3 out 
of 192 missing).
I include below the model and an xyplot that almost does the
2003 Dec 09
3
axes that meet
R v. 1.7.1, Windows 2000.
A particular journal wants me to provide scatter plots with no box, but 
with axes that meet in the lower left corner. It seems as though there must 
be an easy way of doing this, but my reading the help on plot.default, 
axis, and box have not provided any clues. I would be most appreciative of 
any feedback.
Thank you,
Hank Stevens
Dr. Martin Henry H. Stevens,
2003 Dec 02
2
contributed packages not found
Windows 2000, R 1.6.1
   When I try use the menu to download and install new packages, the
   result looks like this:
   {a <- CRAN.packages()
   + install.packages(select.list(a[,1],,TRUE), .libPaths()[1],
   available=a)}
   trying URL `[1]http://cran.r-project.org/bin/windows/contrib/PACKAGES'
   Error in download.file(url = paste(contriburl, "PACKAGES", sep = "/"),
 
2006 Jun 09
1
binomial lmer and fixed effects
Hi Folks,
I think I have searched exhaustively, including, of course R-help (D.  
Bates, S. Graves, and others) and but I remain uncertain about  
testing fixed effects with lmer(..., family=binomial).
I gather that mcmcsamp does not work with Do we rely exclusively on z  
values of model parameters, or could we use anova() with likelihood  
ratios, AIC and BIC, with (or without)
2007 Jan 03
1
mcmcsamp and variance ratios
Hi folks,
I have assumed that ratios of variance components (Fst and Qst in  
population genetics) could be estimated using the output of mcmcsamp  
(the series on mcmc sample estimates of variance components).
What I have started to do is to use the matrix output that included  
the log(variances), exponentiate, calculate the relevant ratio, and  
apply either quantile or or HPDinterval to get
2005 Oct 10
3
Under-dispersion - a stats question?
Hello all:
I frequently have glm models in which the residual variance is much  
lower than the residual degrees of freedom (e.g. Res.Dev=30.5, Res.DF  
= 82). Is it appropriate for me to use a quasipoisson error  
distribution and test it with an F distribution? It seems to me that  
I could stand to gain a much-reduced standard error if I let the  
procedure estimate my dispersion factor (which
2005 Oct 14
1
lattice with predicted values
Dear lattice wizards,
I am trying to figure out how to plot predicted values in xyplot,  
where the intercept, but not the slope, varies among conditioning  
factor levels. I am sure it involves the groups, but I have been  
unsuccessful in my search in Pinhiero and Bate, in the help files, or  
in the archive, or in my attempts on my own.
My example follows:
FACT is a factor with levels a,b,c
2007 May 31
2
Different fonts on different axes
Hi Folks,
How do I get red bold font on my y axis and black standard font on my  
x axis?
plot(runif(10), ylab="Red, Bold?", xlab="Black, standard?")
Any pointers or examples would be great.
Thanks!
Hank
Dr. Hank Stevens, Assistant Professor
338 Pearson Hall
Botany Department
Miami University
Oxford, OH 45056
Office: (513) 529-4206
Lab: (513) 529-4262
FAX: (513) 529-4243
2004 Sep 16
1
geoR/variog4() not returning all directions
Mac OS 10.3.5, R 2.0.0
latest version of geoR
I have an incomplete 5 x 20 spatial array of samples (60 out of 100 
possible locations) for which I would like to calculate directional 
variograms using variog4(). Unfortunately, I can't get it to return all 
4 directions. It returns variograms for 45, 90, and 135 degrees, 
omitting 0 degrees (pi/4, pi/2, 3pi/4, omitting 0). If I specify 0 
2005 Jul 27
4
odesolve/lsoda differences on Windows and Mac
Hi -
I am getting different results when I run the numerical integrator 
function lsoda (odesolve package) on a Mac and a PC. I am trying to 
simulating a system of 10 ODE's with two exogenous pulsed inputs to the 
system, and have had reasonably good success with many model parameter 
sets. Under some parameter sets, however, the simulations fail on the 
Mac (see error message below). The
2004 Feb 09
3
citing a package?
How do I cite a package (not R itself - I know how to do that)? Any 
thoughts or links?
Many thanks in advance?
Hank Stevens
Dr. Martin Henry H. Stevens, Assistant Professor
338 Pearson Hall
Botany Department
Miami University
Oxford, OH 45056
Office: (513) 529-4206
Lab: (513) 529-4262
FAX: (513) 529-4243
http://www.cas.muohio.edu/botany/bot/henry.html
http://www.muohio.edu/ecology/
2006 May 17
1
nlme model specification
Hi folks,
I am tearing my hair out on this one.
I am using an example from Pinheiro and Bates.
### this works
data(Orange)
mod.lis <- nlsList(circumference ~  SSlogis(age, Asymp, xmid, scal),
             data=Orange )
### This works
mod <- nlme(circumference ~  SSlogis(age, Asymp, xmid, scal),
             data=Orange,
             fixed = Asymp + xmid + scal ~ 1,
             start =
2005 Jul 01
2
Simple indexing conundrum
My apologies in advance for my thickness but I can't seem to solve the 
following, seemingly simple, data manipulation problem:
I have a data frame that contains multiple factors and multiple 
continuous response variables, but duplicates of some factor 
combinations. The duplicates contain bad data, so I would like to 
eliminate the duplicates. I would like to retain the entire rows 
2001 Aug 10
1
An applied math question with solve()
I have a math (and maybe an R) question.
I want to find equilibrium population density values for a system of linear
population growth equations (e.g., Pimm and Lawton 1977). The eventual goal
is to
perform stability analysis. I can find the partial differential equations
for the Jacobian matrix, but I get stuck trying finding the equilibriuym pop
densities (X*). Here is the (incorrect?) R code
2001 Aug 01
1
italics and not in main=
R 1.3.0, windows
I've checked archives, and examples in text, mtext, and title.
I am trying to include italicized text in the main title of a figure:
....,
main = "[italics here] species name [italics stop] more plain text"
TIA,
Henry
*****************************
Martin Henry H. Stevens
HStevens at muohio.edu
tel: (513) 529 - 4206
FAX: (513) 529 - 4243
338 Pearson Hall
Botany
2001 Aug 14
1
safe data.restore
(R 1.3.0, ESS, Emacs, Windows)
I would like to import a set of objects exported from S+ v. 6, beta2 using
data.dump, but I want to make sure that it does not overwrite current
objects I am using in R. How would I route the output of data.restore() to
ensure the safety of my current objects?
Thanks very much,
Henry
*****************************
Martin Henry H. Stevens
HStevens at muohio.edu
tel: