Displaying 20 results from an estimated 1000 matches similar to: "PROC MIXED user trying to use (n)lme..."
2002 Mar 29
1
help with lme function
Hi all,
I have some difficulties with the lme function and so this is my problem.
Supoose i have the following model
y_(ijk)=beta_j + e_i + epsilon_(ijk)
where beta_j are fixed effects, e_i is a random effect and
epsilon_(ijk) is the error.
If i want to estimate a such model, i execute
>lme(y~vec.J , random~1 |vec .I )
where y is the vector of my data, vec.J is a factor object
2008 Aug 29
3
extract variance components
HI,
I would like to extract the variance components estimation in lme function
like
a.fit<-lme(distance~age, data=aaa, random=~day/subject)
There should be three variances \sigma_day, \sigma_{day %in% subject } and
\sigma_e.
I can extract the \sigma_e using something like a.fit$var. However, I cannot
manage to extract the first two variance components. I can only see the
results in
2006 Apr 11
1
type II and III Sum square whit empty cells
Dear all
I need to run an anova from a factorial model
y_{ijk}=\alpha_i+\beta_j+(\alpha\beta)_{ij}+e_{ijk}
and calculate type II and III sums of square, but I have an empty
cells, so anova function from package car fail. (I believe)
y<-c(7,13,6,10,8,11,8,3,7,5,65)
a<-as.factor(c(1,1,2,2,3,3,3,1,1,1,2))
b<-as.factor( c(rep(1,7),rep(2,4)) )
table(b,a) # cell (2,3) is empty
2005 Jun 14
1
within and between subject calculation
Dear helpers in this forum,
I have the following question:
Suppose I have the following data set:
id x y
023 1 2
023 2 5
023 4 6
023 5 7
412 2 5
412 3 4
412 4 6
412 7 9
220 5 7
220 4 8
220 9 8
......
and i want to calculate sum_{i=1}^k
sum_{j=1}^{n_i}x_{ij}*y_{ij}
is there a simple way to do this within and between
subject summation in R?
2006 Nov 03
5
ANOVA in Randomized-complete blocks design
Dear all,
I am trying to repeat an example from Sokal and Rohlfs "Biometry" --
Box 11.4, example of a randomized-complete-blocks experiment.
The data is fairly simple:
series genotype weight
1 pp 0.958
1 pb 0.985
1 bb 0.925
2 pp 0.971
2 pb 1.051
2 bb 0.952
3 pp 0.927
3 pb 0.891
3 bb 0.892
4
2005 Jun 15
2
need help on computing double summation
Dear helpers in this forum,
This is a clarified version of my previous
questions in this forum. I really need your generous
help on this issue.
> Suppose I have the following data set:
>
> id x y
> 023 1 2
> 023 2 5
> 023 4 6
> 023 5 7
> 412 2 5
> 412 3 4
> 412 4 6
> 412 7 9
> 220 5 7
> 220 4 8
> 220 9 8
> ......
>
Now I want to compute the
2011 Aug 26
1
matrix bands
Dear R developers,
I was looking for a function analogous to base::diag() for getting and
setting bands of a matrix. The closest I could find was Matrix::band(),
but this was not exactly what I wanted for two reasons. Firstly,
Matrix::band() returns a matrix rather than just the specified band.
Secondly, Matrix::band() cannot be used for setting the values for a
matrix band.
Setting or
2004 Nov 23
2
IFELSE across large array?
Dear all,
As our previous email did not get any response, we try again with a
reformulated question!
We are trying to do something which needs an efficient loop over a huge
array, possibly functions such as apply and related (tapply,
lapply...?), but can't really understand syntax and examples in
practice...i.e. cant' make it work.
to be more specific:
we are trying to apply a mask
2009 Oct 27
1
Rjava, RImageJ, and/or S4 question.
I am out of my league with this question. The following code starts the java imaging program ImageJ from within R, and displays an image (assuming ImageJ is installed on your computer).
library(RImageJ)
img <- IJ$openImage( file.choose() ) #pick an available .tif file
img$show() # make the image object visible
# An image is now displayed
# find out about the objects involved
>
2009 Oct 17
2
Recommendation on a probability textbook (conditional probability)
I need to refresh my memory on Probability Theory, especially on
conditional probability. In particular, I want to solve the following
two problems. Can somebody point me some good books on Probability
Theory? Thank you!
1. Z=X+Y, where X and Y are independent random variables and their
distributions are known.
Now, I want to compute E(X | Z = z).
2.Suppose that I have $I \times J$ random number
2003 Apr 02
2
lme parameterization question
Hi,
I am trying to parameterize the following mixed model (following Piepho
and Ogutu 2002), to test for a trend over time, using multiple sites:
y[ij]=mu+b[j]+a[i]+w[j]*(beta +t[i])+c[ij]
where:
y[ij]= a response variable at site i and year j
mu = fixed intercept
Beta=fixed slope
w[j]=constant representing the jth year (covariate)
b[j]=random effect of jth year, iid N(0,sigma2[b])
a[i]=random
2011 Jan 03
1
Greetings. I have a question with mixed beta regression model in nlme.
*Dear R-help:
My name is Rodrigo and I have a question with nlme package
in R to fit a mixed beta regression model. The details of the model are:
Suppose that:*
*j in {1, ..., J}* *(level 1)*
*i in {1, ..., n_j}* *(level 2)*
*y_{ij} ~ Beta(mu_{ij} * phi_{ij}; (1 - mu_{ij}) * phi_{ij})
y_{ij} = mu_{ij} + w_{ij}
*
*with*
*logit(mu_{ij}) = Beta_{0i} + Beta_{1i} * x1_{ij} + b2 * x2_{ij}
2011 Jan 03
0
Greetings. I have a question with mixed beta regression model in nlme (corrected version).
*Dear R-help:
My name is Rodrigo and I have a question with nlme package
in R to fit a mixed beta regression model. I'm so sorry. In the last
email, I forgot to say that W is also a unknown parameter in the mixed
beta regression model. In any case, here I send you the correct formulation.
**
Suppose that:*
*j in {1, ..., J}* *(level 1)*
*i in {1, ..., n_j}* *(level 2)*
*y_{ij} ~
2002 Aug 12
0
help with pseudo-random numbers
Dear People,
I have a vexing problem related to pseudo-random number generation, and
would appreciate any help and advice. This problem is not directly related
to R, and the only reason I am posting it to this list is that my
implementation is using R. Let me describe my problem by giving an
example, that is close to what I am trying to do.
Suppose we are given a stream of pseudo-random numbers,
2011 Feb 04
2
Avoiding two loops
Hello,
I have a R code for doing convolution of two functions:
convolveSlow <- function(x, y) {
nx <- length(x); ny <- length(y)
xy <- numeric(nx + ny - 1)
for(i in seq(length = nx)) {
xi <- x[[i]]
for(j in seq(length = ny)) {
ij <- i+j-1
xy[[ij]] <- xy[[ij]] + xi * y[[j]]
}
}
xy
}
How do I reduce the 2
2005 Aug 27
2
Defining an ex-gaussian PDF
How does one define PDFs as yet undefined in R, such as the ex-
gaussian, the sum of two RVs, one exponential, one Gaussian? The PDF
would then be the convolution of an exponential PDF, dexp(), and a
normal, dnorm().
Kindly cc me in your reply to r-help.
Thanks,
_____________________________
Professor Michael Kubovy
University of Virginia
Department of Psychology
USPS: P.O.Box 400400
2006 Oct 25
1
cloud() works but wireframe() is blank
Per the message from Alexander Nervedi, 29 April 2006:
> I have to be making a riddiculously silly ommission.
> when I run the fillowing i get the cloud plot ok. But I cant figure
> out what I am missing out when I call wireframe.
> Any help would be appreciated.
> x<-runif(100)
> y<-rnorm(100)
> z<-runif(100)
> temp <-data.frame(x,y,z)
>
2011 Apr 27
6
Assignments inside lapply
Dear all I would like to ask you if an assignment can be done inside a lapply statement.
For example
I would like to covert a double nested for loop
for (i in c(1:dimx)){
for (j in c(1:dimy)){
Powermap[i,j] <- Pr(c(i,j),c(PRX,PRY),f)
}
}
to something like that:
ij<-expand.grid(i=seq(1:dimx),j=(1:dimy))
unlist(lapply(1:nrow(ij),function(rowId) { return
2011 Sep 12
6
Rv: Re: Cosinor Analysis
--- El lun, 12/9/11, Cristalina <pa100cia77@yahoo.es> escribió:
De: Cristalina <pa100cia77@yahoo.es>
Asunto: Re: [R-es] Cosinor Analysis
Para: "Carlos Ortega" <coforfe@gmail.com>
Fecha: lunes, 12 de septiembre, 2011 08:43
Hola,
Carlos, muchas gracias.
El método empleado en http://tolstoy.newcastle.edu.au/R/e6/help/09/01/0626.html (el url que se referencia
2012 Oct 29
2
Two-way Random Effects with unbalanced data
Hi there,
I am looking to fit a two-way random effects model to an *unblalanced*
layout,
y_ijk = mu + a_i + b_j + eps_ijk,
i=1,...,R, j=1,...,C, k=1,...,K_ij.
I am interested first of all in estimates for the variance components,
sigsq_a, sigsq_b and sigsq_error.
In the balanced case, there are simple (MM, MLE) estimates for these; In the
unbalanced setup,