Displaying 20 results from an estimated 3000 matches similar to: "I need course in R"
2009 Apr 09
1
reading an image and adding a legend
Hi all,
I would like to
1. Read in an arcmap image into R (I can export pretty much any type of image jpeg, bitmap etc from arcmap)
2. Use R to create a nice colour legend in the plot
First of all, Is this possible?
So far I'm stuck on point 1. I have tried read.pnm() from pixmap and read.jpeg() from rgl.
the pnm example provided works fine
x <-
2009 May 18
9
Concatenating two vectors into one
Dear users,
a very simple question:
Given two vectors x and y
x<-as.character(c("A","B","C","D","E","F"))
y<-as.factor(c("1","2","3","4","5","6"))
i want to combine them into a single vector z as A1, B2, C3 and so on.
z<-x*y is not working, i tried several others
2009 Feb 19
4
type III effect from glm()
Hi all,
This could be naivety/stupidity on my part rather than a problem with model output, but here goes....
I have fitted a fairly simple model
m1<-glm(count~siteall+yrs+yrs:district,family=quasipoisson,weights=weight,data=m[x[[i]],])
I want to know if yrs (a continuous variable) has a significant unique effect in the model, so I fit a simplified model with the main effect ommitted...
2006 Nov 16
1
How Aggegate Data in R
Hello:
When I use SPSS I execute the AGGREGATE DATA comand for the next data:
2112141123212213212213334
3143244113442312121213344
2114141123112214212113344
2112211122212413421213221
3114444123442414343413344
2312231223212222323223322
2143241123212313131213234
2113241113212313222213333
2113141123112214212113344
2114141123412111114413344
2113211122342314222313234
2114141123112414212113344
2009 May 29
1
data manipulation involving aggregate
hi all,
I often have a data frame like this example
data.frame(sq=c(1,1,1,2,2,3,3,3,3),area=c(1,2,3,1,2,3,1,2,3),habitat=c("garden","garden","pond","field","garden","river","garden","field","field"))
for each "sq" I have multiple "habitat"s each with an associated "area".
I
2009 Mar 10
1
help structuring mixed model using lmer()
Hi all,
This is partly a statistical question as well as a question about R, but I am stumped!
I have count data from various sites across years. (Not all of the sites in the study appear in all years). Each site has its own habitat score "habitat" that remains constant across all years.
I want to know if counts declined faster on sites with high "habitat" scores.
I can
2008 Dec 18
1
inserting zero instances with zeroes in a matrix
Hi all,
Suppose I had the below example where a survey was carried out recording the number of each type of pet in each house
count<-c(2,1,2,1,2,3,4)
house<-c("house1","house1","house2","house3","house4","house4","house4")
2009 Jan 20
5
Error message from CV.GLM
Dear list members.
I have problems with the usage of cv.glm from the boot package. Here are some parts of the script I wanted to use:
data <- read.table("selected_2D.csv", header=TRUE, sep=",")
?
glm.fitted <- glm("ydata$ y ~ 1 + density + vsurf_ID6 + vsurf_S ", data=data)
error <- cv.glm(data=data, glm.fitted, K=6)
ydata$y is a separate data set, where
2009 May 06
11
Do you use R for data manipulation?
Is R an appropriate tool for data manipulation and data reshaping and data
organizing? I think so but someone who recently joined our group thinks not.
The new recruit believes that python or another language is a far better
tool for developing data manipulation scripts that can be then used by
several members of our research group. Her assessment is that R is useful
only when it comes to data
2003 Apr 12
3
WG: Samba 2.2.7a and XP pro
Dear Michael,
I just have the same problem you have with samba 2.2.3a on a Suse 8.0
machine and win xp pro. Besides I performed all the steps below.
>From my postings I learned that the prob might have something to do with
a wrong mapping in smbusers file. It seems to me that the workstation
account is mapped to user nobody.
Up to now I was not able to solve the prob.
Do you have any ideas
2008 Jan 17
4
things that are difficult/impossible to do in SAS or SPSSbut simple in R
Good morning,
I use SAS and R/S-Plus as my primary tools so I have a lot of experience with these programs. By far and away, SAS is superior for handling the "messy" datasets, but also the very large ones. I work at times with datasets in the hundreds of thousands (and on occasion, millions) of records. SAS, and especially PROC SQL, are invaluable for this. But once I get to
2008 Sep 28
2
best material for programmers?
Hello,
What is the best material(book, pdfs, ...) for programmers, who have
extensive experience in other programming languages, to learn R
programming? I think there are many materials on how to use R for
specific statistical jobs, but I haven't seen any material
particularly designed for R programming.
Thanks.
2007 Oct 09
2
Help with gamm errors
Dear All
Hopefully someone out there can point out what I am missing! I have a
(large, several hundred) dataset of gardens in which over two years the
presence/absence of a particular bird species is noted each week. I have
good reason to believe there is a difference between the two years in the
weekly proportion of gardens and would like to assess this, before going on
to look in more detail at
2007 Nov 21
2
Reconstruct array dataset
Hi there
I have an interesting problem:
My csv file is of array dimensions [12,50], but it was saved the wrong way: there should be only 11 colums. What happens now if I read it into R is that the whole data set is shifted ( in the first row, the last column contains already the first value of the supposed second row and so on...)
how can I tell R to switch after 11 read values to the next row,
2008 Jan 14
6
Ceiling to the nearest ten?
R-users,
Is there a function for ceiling to the nearest ten?
a <- 1:10*4
a
[1] 4 8 12 16 20 24 28 32 36 40
The resulting vector should look like this ("ceiling to the nearest ten")
[1] 10 10 20 20 20 30 30 40 40 40
Thanks in advance
Lauri
2006 Aug 10
1
help with structuring random factors using lmer()
Hi,
I am an R beginner and having problems structuring my REML models. I have
a model with
y=weight
x1=time
x2=timesquared
id=individual identity
I need to structure the model such that in the random effects there is a
constant intercept for all individuals but a separate individual slope for
both x1 and x2 (a coefficient score for every individual).
2007 Nov 26
1
spss, string factors, selecting
Hi,
I am having trouble with a large dataset I am importing from SPSS.
The problem is I have to merge two datasets (which seems to be
working OK) then select rows based on attributes. I have a column
with either blank cells, B or E entered. I want to select all rows
with E. I have other columns with numerical data which I will then do
analyses on.
data[column==" E"] does not
2003 Apr 10
7
Samba 2.2.7a and XP pro
I have read over the lists and search the web, I know this question has
been asked before, but I've not been able to fix my problem so I'll ask
here.
I have been successful in joining the XP machine to the domain however it
when I try to login to the domain windows instantly kicks up the message:
"Windows cannot connect to the domain, either because the domaincontroller
is down or
2006 Aug 16
1
[SPAM] - RE: REML with random slopes and random intercepts giving strange results - Bayesian Filter detected spam
Can you provide the summary(m2) results?
> -----Original Message-----
> From: Simon Pickett [mailto:S.Pickett at exeter.ac.uk]
> Sent: Wednesday, August 16, 2006 7:14 AM
> To: Doran, Harold
> Cc: r-help at stat.math.ethz.ch
> Subject: [SPAM] - RE: [R] REML with random slopes and random
> intercepts giving strange results - Bayesian Filter detected spam
>
> Hi again,
2006 Aug 24
1
help: trouble using lines()
Hi R experts,
I have been using ReML as follows...
model<-lmer(late.growth~mtf+year+treat+hatch.day+hatch.day:year+hatch.day:treat+
mtf:treat+ treat:year+ year:treat:mtf+(1|fybrood), data = A)
then I wanted to plot the results of the three way interaction using
lines() as follows...
tmp<-as.vector(fixef(model))
graph1<-plot(mtf,fitted(f2), xlab=list("Brood Size"),