Prof Brian Ripley wrote:
On Sat, 9 Feb 2008, Michael Kubovy wrote:
On Feb 9, 2008, at 4:41 PM, Prof Brian Ripley wrote:
On Sat, 9 Feb 2008, Michael Kubovy wrote:
How do I enter 'much greater than' and 'much less than' symbols in an
expression?
Those are not in
mohamed nur anisah [EMAIL PROTECTED] [Fri, Feb 08, 2008 at 04:42:41PM CET]:
Dear lists,
I'm in my process of learning of writing a function. I tried to write a
simple functions of a matrix and a vector. Here are the codes:
mm-function(m,n){ #matrix function
Dear all,
I have a data set with four different groups, for each group I have several
observation (number of observation in each group are unequal), and I want to
test if there are some differences in the values between the groups.
What will be the most proper way to test this in R?
Regards
Greetings,
I'm having a problem with something that I think is very simple - I'd
like to be able to use the 'sapply' and 'by' functions in 1 function
to be able (for example) to get regression coefficients from multiple
models by a grouping variable. I think that I'm missing something
that is
By passing new to fxa via the second argument of fxa, new is not being
subsetted hence the error. Try this:
by(new, new$sex, function(x) sapply(x[1:2], function(y) coef(lm(y ~ Pred, x)))
Actually, you can do the above without sapply as lm can take a matrix
for the dependent variable:
by(new,
Actually thinking about this, not only do you not need sapply but you
don't even need by:
new2 - transform(new, sex = factor(sex))
coef(lm(as.matrix(new2[1:2]) ~ sex/Pred - 1, new2))
On Feb 10, 2008 8:43 AM, Gabor Grothendieck [EMAIL PROTECTED] wrote:
By passing new to fxa via the second
Dear Yongfu He,
If you mean a recursive structural-equation model, then if you're willing to
assume normally distributed errors, equation-by-equation OLS regression,
using lm(), will give you the full-information maximum-likelihood estimates
of the structural coefficients. You could also use the
On Feb 10, 2008 2:29 AM, Maura E Monville [EMAIL PROTECTED] wrote:
I saw there exists an R version for Mac/OS.
I'd like to hear from someone who is running R on a Mac/OS before venturing
on getting the following computer system.
I am in the process of choosing a powerful laptop 17 MB PRO
Hi Dani,
it would be better to start with a question you are trying to ask of your
data rather than trying to figure out what a particular function does. with
your variables and model, even if the component terms were not significant,
they must in the model or the product of sunlight and aspect
I get the digest, so I apologize if this is a little late.
For your situation (based on the description and what I think your code
is doing, more on that below), it looks like you are modeling a Poisson
flow where the number of hits per unit time is a random integer with
some mean value.
If I
On Feb 10, 2008 8:25 AM, Gabor Grothendieck [EMAIL PROTECTED] wrote:
Actually thinking about this, not only do you not need sapply but you
don't even need by:
new2 - transform(new, sex = factor(sex))
coef(lm(as.matrix(new2[1:2]) ~ sex/Pred - 1, new2))
Although that's a very slightly
Hello,
Thanks that helped for poisson.
When I changed method to ML it worked for poisson but when I used that for
nbinomial I got errors.But why is this happening?
gf-goodfit(binCount,type= poisson)
summary(gf)
Goodness-of-fit test for poisson distribution
X^2 df P(
Although that's a very slightly different model, as it assumes that
both sexes have the same error variance.
But the output are the coefficients and they are identical.
For the sake of an example I'm sure that David simply omitted the part
of his analysis where he looked at the standard
On 10/02/2008 1:07 PM, Erin Hodgess wrote:
Hi R People:
I sure that this is a really easy question, but here goes:
I'm trying to build a package that will run on both Linux and Windows.
However, there are several commands in a section that will be
different in Linux than they are in
Hi R People:
I sure that this is a really easy question, but here goes:
I'm trying to build a package that will run on both Linux and Windows.
However, there are several commands in a section that will be
different in Linux than they are in Windows.
Would I be better off just to build two
Hi R People:
When performing PCA, should I use prcomp, princomp or fast.prcomp, please?
thanks.
Erin
--
Erin Hodgess
Associate Professor
Department of Computer and Mathematical Sciences
University of Houston - Downtown
mailto: [EMAIL PROTECTED]
__
On my widows XP computer, W
From my windows XP system running R 2.6.1:
version
_
platform i386-pc-mingw32
arch i386
os mingw32
system i386, mingw32
On 10-Feb-08 18:07:56, Erin Hodgess wrote:
Hi R People:
I sure that this is a really easy question, but here goes:
I'm trying to build a package that will run on both Linux and Windows.
However, there are several commands in a section that will be
different in Linux than they are in
Hi,
I went ahead and implemented something. However:
- I cannot garantie it gives correct results since, unfortunately, the
data used in Syrjala 1996 is not published along with the paper. To
avoid mistakes, I started by coding things in a fast and simple way
and then tried to optimize the
sub(-, --, v, fixed=TRUE)
See ?sub.
Gabor
On Sun, Feb 10, 2008 at 02:14:48PM -0500, Michael Kubovy wrote:
Dear R-helpers,
How do I transform
v - c('insd-otsd', 'sppr-unsp')
into
c('insd--otsd', 'sppr--unsp')
?
_
Professor Michael Kubovy
University of
Dear R-helpers,
How do I transform
v - c('insd-otsd', 'sppr-unsp')
into
c('insd--otsd', 'sppr--unsp')
?
_
Professor Michael Kubovy
University of Virginia
Department of Psychology
USPS: P.O.Box 400400Charlottesville, VA 22904-4400
Parcels:Room 102
You just have too large a vector for your memory.
There is not much you can do with an object of 500 MG.
You have over 137 million combinations.
What are you trying to do with this vector?
--- Oscar A [EMAIL PROTECTED] wrote:
Hello everybody!!
I'm from Colombia (South America) and I'm new
Dear R People:
Sorry for the off-topic. Could someone recommend a good reference for
using the EM algorithm on mixed models, please?
I've been looking and there are so many of them. Perhaps someone here
can narrow things down a bit.
Thanks in advance,
Sincerely,
Erin
--
Erin Hodgess
Hello
I have 2 data frames df1 and df2. I would like to create a
new data frame new_df which will contain only the common rows based on the
first 2
columns (chrN and start). The column score in the new data frame
should
be replaced with a column containing the average score (average_score) from
Hi, Erin:
Have you looked at Pinheiro and Bates (2000) Mixed-Effects Models
in S and S-Plus (Springer)?
As far as I know, Doug Bates has been the leading innovator in
this area for the past 20 years. Pinheiro was one of his graduate
students. The 'nlme' package was developed
On 10/02/2008, joseph [EMAIL PROTECTED] wrote:
Hello
I have 2 data frames df1 and df2. I would like to create a
new data frame new_df which will contain only the common rows based on the
first 2
columns (chrN and start). The column score in the new data frame
should
be replaced with a
joseph [EMAIL PROTECTED] wrote in
news:[EMAIL PROTECTED]:
I have 2 data frames df1 and df2. I would like to create a
new data frame new_df which will contain only the common rows based
on the first 2 columns (chrN and start). The column score in the new
data frame should
be replaced with a
On 2/10/08, Erin Hodgess [EMAIL PROTECTED] wrote:
When performing PCA, should I use prcomp, princomp or fast.prcomp, please?
You can take a look here [1] and here [2] for some short references.
From the first page: Principal Components Analysis (PCA) is available
in prcomp() (preferred) and
I think that what you want do is stepwise, see step function
On 09/02/2008, AliR [EMAIL PROTECTED] wrote:
Thank you, can you suggest wht is the shortest way to store the combination
with min residual error term?
AliR wrote:
http://www.nabble.com/file/p15359204/test.data.csv
Dear colleagues,
I'd like to reshape a datafame in a long format to a wide format, but
I do not quite get what I want. Here is an example of the data I've
have (dat):
sp - c(a, a, a, a, b, b, b, c, d, d, d, d)
tr - c(A, B, B, C, A, B, C, A, A, B, C, C)
code - c(a1, a2, a2, a3, a3, a3, a4, a4, a4,
reshape(dat, direction=wide, timevar=tr, idvar=c(id, code,sp ))[,2:6]
But, I don't understand why you use reshape
On 10/02/2008, juli pausas [EMAIL PROTECTED] wrote:
Dear colleagues,
I'd like to reshape a datafame in a long format to a wide format, but
I do not quite get what I want. Here is
This isn't really well defined. Suppose we have two rows that
both have a, a2 and a value for B. Now suppose we have
another row with a,a2 but with a value for C. Does the third row
go with the first one? the second one? a new row? both the first
and the second?
Here is one possibility but
dropterm() is a tool for model building, not primarily for significance
testing.
As the name suggests, it tells you what the effect would be were you to
drop each *accessible* term in the model as it currently stands. By
default it displays the effect on AIC of dropping each term, in turn,
from
Hi:
I have a query related to the J and Jcross functions in the SpatStat
package.
I use J to finding indications of clustering in my data, and Jcross
to look for dependence between point patterns.
I use the envelope function to do Monte Carlo tests to look for
significance.
So far so good.
Hello
I'm doing some experiments with the various histogram functions and I
have a two questions about the prob option and binning.
First, here's a simple plot of my data using the default hist()
function:
hist(data[,1], prob = TRUE, xlim = c(0, 35))
http://go.sneakymustard.com/tmp/hist.jpg
On 10/02/2008 8:14 PM, Andre Nathan wrote:
Hello
I'm doing some experiments with the various histogram functions and I
have a two questions about the prob option and binning.
First, here's a simple plot of my data using the default hist()
function:
hist(data[,1], prob = TRUE, xlim =
Andre,
Regarding your first question, it is by no means clear there is anything
to fix, in fact I'm sure there is nothing to fix. The fact that the
height of any bar is greater than one is irrelevant - the width of the
bar is much less than one, as is the product of height by width. Area
is
Hi All,
I am scheduled to teach a graduate course on research methods in
health sciences at a university. While drafting the course proposal, I
decided to include a brief introduction to R, primarily with an
objective to enable the students to do data analysis using R. It is
expected that
Comment 1 raises a real issue. R is just a tool. Too often people do
confuse the tool with the real skill that the people who use it should
have. There are plenty of questions on R-help that demonstrate this
confusion. It's well worth keeping in mind and acting upon if you can
see a problem
Hello Arin,
If your future students do not know statistics, you might consider
buffering their introduction to R with the help of a GUI package, such
as Rcmdr (if functionality is missing, you could add it yourself via
the plugin infrastructure). Another way to help students would be to
direct
Dear all,
I am new to R. I am using the impute package with data contained in csv
file.
I have followed the example in the impute package as follows:
mydata = read.csv(sample_impute.csv, header = TRUE)
mydata.expr - mydata[-1,-(1:2)]
mydata.imputed - impute.knn(as.matrix(mydata.expr))
The
R is just a tool, but so is English. R is the platform of
choice for an increasing portion of people involved in new statistical
algorithm development. R is not yet the de facto standard for nearly
all serious research internationally, to the extent that English is.
However, I believe
Hi
Hoping someone can help me (a newbie).
I am trying to construct a tree using tree() in package tree. One of the
fields is a factor field (owner), with many levels. In the resulting tree, I
see many NA's (see below), yet in the actual data there are none.
rr200.tr - tree(backprof ~
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