Displaying 20 results from an estimated 2000 matches similar to: "error ellipse"
2007 Apr 27
2
proportional sampling
Dear All,
I wonder if you could help me.
I have a table with a series of sites that I would like to sample from.
The table has 5 columns:
ID
X Coordinate
Y Coordinate
Value
Factor
The conditions are that each site can be selected more than once and the
probability of it being selected (or sampled) is proportional to a factor
located in column 'Factor'
I am novice in terms of R, and
2006 Feb 09
2
nice log-log plots
Dear All,
I am trying to produce log-log plots in R and I was wondering if any of you have a 'template' for generating these with 'nice' labels and log-log grids?
I know I can set up axes individually and use the intervals I want, however, I will be producing a large number of these plots and would not like to do this manually for each of them + I am very new to R and at the
2002 Feb 25
5
another basic ?
i am sure that there is a simple solution that i am just overlooking, but
there is no logical test for =
there is one for != and >,<, >=, <=...
what do i do if i need to check if something IS EQUAL
or is there an easy way, in working with a matrix of size n x 3, to sort
the matrix by one of the columns?
specifically what i am trying to do is i have a matrix with individual and
2001 Aug 24
3
matching character substrings
Hello,
Is there a function for searching a string for a given character? For
example, I have
transcriptions like
tsibi
tSibi
tibi
kibi
I want to search the character object for the presence of 's' or 'S' or
'k'.
I thought perhaps pmatch(c("k", "S", "s"), x) would work for me, but it
wants to compare from the start of the string and returns
2002 Mar 20
3
check without loop
i am probably just missing this one, but how can i check to see if a number
is a part of a vector?
i know i could do a loop checking for equivalence for each element, but i am
thinking that there must be a simpler way to do it than that ( i think that
i have even done it in the past, but can't remember how!)
thanks
what i am working with:
(hope this makes sense)
arclist
[1] 2 2 6
2002 Feb 18
3
i think i asked the wrong ?
me again, new to R, haven't programmed in a long time at all
sorry to ask what is probably basic
a while ago i asked how to remove an element from a list
apparently what i am using is not a list but a vector, didn't realize there
was a list data type
could also use a matrix for what i am doing, is there a way to remove
single elements from either of those?
thanks for any help, if i was
2009 Dec 20
2
as.Date question
All!
This piece of code:
zzz1 <- as.POSIXct("1999-03-18", tz="CET")
zzz2 <- as.POSIXlt("1999-03-18", tz="CET")
zzz1 == zzz2
as.Date(zzz1)
as.Date(zzz2)
yields TRUE for "zzz1==zzz2", but the two dates returned by as.Date are different:
> as.Date(zzz1)
[1] "1999-03-17"
> as.Date(zzz2)
[1] "1999-03-18"
I'm
2010 Jan 09
1
lattice, add text to xyplot
Hello listers,
Does anybody know how to add text to an xyplot without whipping out
the existing curve?
That's all.
For instance,
Lets say you generate a graph like this
A <- data.frame(x = rnorm(100), y = rnorm(100))
xyplot(y ~ x, data = A)
How would you add 'Hello world'?
I tried 6.02E23 different partial solutions found on the web and
failed. I just need one EXAMPLE that
2010 May 11
1
functions sample() and S.SI()
Hello,
I need to select a sample from a small population using simple random
sampling without replacement. I've found two possibilities in R, the
function sample() and the function S.SI() in the package
TeachingSampling, but I don't know which one is better.
Can someone help me?
Thank you
--
Lourdes Molera Peris
M?todos Cuantitativos para la Econom?a y la Empresa
Facultad de Econom?a
2009 Jun 19
2
correlation between categorical data
Hi all,
In a data-frame, I have two columns of data that are categorical.
How do I form some sort of measure of correlation between these two columns?
For numerical data, I just need to regress one to the other, or do
some pairs plot.
But for categorical data, how do I find and/or visualize correlation
between the two columns of data?
Thanks!
2009 Nov 26
2
Multivariate problems . . . with 200 resposes variables and 1 explanatory variable
How should I analysis it in R ???? all the resposes variables are ordinal
from 0 to 10. and the explanatory variable is a factor ...
--
View this message in context: http://old.nabble.com/Multivariate-problems-.-.-.-with-200-resposes-variables-and-1-explanatory-variable-tp26522912p26522912.html
Sent from the R help mailing list archive at Nabble.com.
2002 Apr 29
2
efficiency
i have a set of files that i am reading into R one at a time and applying
to a function that i have written
where each is a 'table' n (columns) x 10000 (rows)
n varies across the files and most of the rows only have data in the first
few columns
currently i am reading them in with the command:
read.table(file="2.75.0.997.1", header=FALSE, sep="", skip=13, fill=,
2011 Feb 06
1
random interaction effect in lmer
Hi dears while modeling an interaction random effect in lmer i receive the
instantaneous error message
> ldlM4<-lmer(ldl~rt*cd4+age+rf+pharmac+factor(hcv)+
+ hivdur+(rt:cd4|id),na.action=na.omit,REML=F)
*Warning message:
In mer_finalize(ans) : false convergence (8)
*
I think the matter lies in syntax, 'cause i sistematically receive the same
message even when changing response...
PS:
2010 Jan 22
1
Sata and R users GLM methods translation
Hello,
I am learning R and I am fluent in Stata and I try to translate part of my
Stata code to R to check the reliability of the data under R. I have a
proportion variable as a dependent variable pQSfteHT . Independent variables
are dummies for two categorical variables called dQSvacrateHTQuali3 and
cluster_3. I am fitting a model with the Stata command below:
glm pQSfteHT dQSvacrateHTQuali3_2
2002 Mar 20
7
how does while work
i am having some problems with a program that i am writing and i think that
knowing how the while command works will help me to figure out where i am
going wrong
*when do you get kicked out of a while loop?*
(i.e., in the following example what would the final value of 'a' be?) i
thought it would be 99 but running it in R i get 101 (and 101 for x too!)
while (x <100) {
for (i in
2011 Sep 08
2
The elegant way to test if a number is a whole number
Hi,
x <- 0.2*5
is.integer(x)
gives me FALSE because R stores it as a float number, right?
Is there an elegant way to work around that problem? Right now
I'm using
x <- 0.2*5
round(x) == x
which returns TRUE. But more strictly I should use all.equal(),
right?
I somehow just don't like the--pardon--ugliness of those pieces
of code. Maybe there is a beautiful
2009 Aug 03
2
lme funcion in R
Hi, R users,
I'm using the "lme" function in R to estimate a 2 level mixed effects
model, in which the size of the subject groups are different. It turned out
that It takes forever for R to converge. I also tried the same thing in SPSS
and SPSS can give the results out within 20 minutes. Anyone can give me some
advice on the lme function in R, especially why R does not converge?
2004 Jun 25
7
circle / oval / semicircle ?
hi: where would I find facilities to draw circles, ovals, and
semicircles? (or should I construct them myself using curve?)
regards, /ivo
2003 Apr 18
2
Question about PAM clustering method
Hello everyone. I just started learning R for clustering analysis in my
research project. I tried k-means method and PAM method, both of which
were properly processed with my data. I have some questions about PAM
graphical output.
Suppose to do the commands shown below;
pm<-pam(D, 6)
plot(pm)
I got two charts after prompted. In the first chart, 6 oval clusters are
drawn together
2009 Nov 28
2
R on Large Data Sets (again)
Dear R users,
I’ve search the R site for help on this topic but it is hard to find a
precise answer for my questions.
Which are the best options to overcome the RAM memory limitation problems
when using R on “large” data sets (such as 2 or 3 million records)?
- Is the free available version of R (as opposed to the one
provided by REvolution Computing) compatible with a windows 64-bit