Displaying 20 results from an estimated 6000 matches similar to: "run setwd at the launch of R"
2007 Mar 01
7
count the # of appearances...
Hi there,
is there a possibility to count the number of appearances of an
element in a vector ?
i mean of any given element.. deliver all elements which are exactly
xtimes in this vector ?
thx in advance !!
2008 Jul 12
5
shapiro wilk normality test
Hi everybody,
somehow i dont get the shapiro wilk test for normality. i just can?t
find what the H0 is .
i tried :
shapiro.test(rnorm(5000))
Shapiro-Wilk normality test
data: rnorm(5000)
W = 0.9997, p-value = 0.6205
If normality is the H0, the test says it?s probably not normal, doesn
?t it ?
5000 is the biggest n allowed by the test...
are there any other test ? ( i know qqnorm
2010 Apr 28
7
operator problem within function
Dear all,
i have a problem with processing dataframes within a function using the "$".
Here´s my code:
recode_items = function(dataframe,number,medium=2){
# this works
q<-paste("columna",number,sep="")
# this does not work, particularly because "dataframe" is not processed
# dataframe should be: givenframe$columnagivennumber
2007 Feb 27
5
Multiple conditional without if
Dear all,
i am stuck with a syntax problem.
i have a matrix which has about 500 rows and 6 columns.
now i want to kick some data out.
i want create a new matrix which is basically the old one except for all
entries which have a 4 in the 5 column AND a 1 in the 6th column.
i tried the following but couldn´t get a new matrix, just some wierd
errors:
2008 Sep 23
3
odds ratio: how to create reference
HI there,
i know this is a basic question, though i need some help because this
is somewhat away from my current issue, but nevertheless interesting
to me... Lets assume i have some estimated probabilities, say
estimated by a logit model. i know i can also state them as an odds
ratio.
Now i?d like to state these odds ratios as a reference to a specific
outcome of my investigated
2007 Mar 07
5
hwo can i get a vector that...
dear all,
how can i get a vector that shows the number of the column of matrix
that contains the maximum of the row ??
can?t believe in need a loop for this...
i have a 100 x 3 matrix and want to get a 100 x 1 vector with values
1,2,3 .
there must be a simple solution. i just cannot find it. i think am
searching on the wrong end.
thx for help in advance.
m.
2010 Jun 01
3
lapply with functions with changing parameters
Dear all,
I am trying to avoid a for loop here and wonder if the following is possible:
I have a data.frame with 6 columns and i want to get a cross-correlogram (by using ccf) . Obivously ccf only accepts two columns at once and then returms a list.
In fact, with a for loop i?d do the following
for (i in 1:6) {
x[[i]]=ccf(mydf[,i],mydf[,6])
}
Is there any chance to the same with
2008 Sep 17
3
t-test between percentages
Hi all,
though i know this is a simple question, i really hope someone could.
I am just trying to compare percents respectively the difference in
percents by a simple test. t.test usually compares means and is
working like it is supposed to be. Now i wonder how i can use a test
in R to test for significant difference between two percentages.
2010 Feb 03
1
plm package index
Dear all,
i just wonder if there´s a way to use a two column time index field in plm package.
the manual says the following concerning data indexing:
a character vector of length two containing the names of the individual and the time
index,
What would y´all do with a quarterly dataset that contains one column for the period and one for the year. Do I have to convert it to one single date
2009 Jan 13
5
indexing question
Hi all,
i have a pretty easy indexing question, at least i believe so. The
main reason i post it here, is that brackets and $ are hard to google.
How do I index correctly, if i just want to display the whole dataset
conditioned on the fact that some particular column equals one.
I know i can do something like: data$somecolumn[data$particularcol
==1] . That will show all "some
2006 Jul 20
2
function names in a vector used by for (){} character problem ?
Hi there,
i´m have vector of kernels. just like:
kernels = c('gauss','epan','rectangular')
i know there are density.default$kernels, but thats not my question
here. my own kernel functions are running and working.
my problem is the following is not working:
dev.off()
par(mfrow=c(3,3))
for(i in 1:length(bw))
{
for(j in 1:length(kernels))
{
2008 Nov 28
2
editor for MacOS X
Hi all,
just wondered again, if there is some R editor for Mac OS X comparable
to TINN-R on windows.
thx in advance..
2006 Nov 24
2
vector problem
Hello out there,
i am not yet that experienced and trying to my best on a real survey.
but i am stuck with a little matrix / vector problem.
my vector of answers could have a length of 3 or only one. i want to
rbind all the answers into one matrix. (one vector for each participant)
answers vectors for one participant could look like:
p1: 100
p2: 20 80
p3: 40 10 50
i have the following
2008 Sep 18
5
propensity score adjustment using R
Hi all,
i am looking to built a simple example of a very basic propensity
score adjustment, just using the estimated propensity scores as
inverse probability weights (respectively 1-estimated weights for the
non-treated). As far as i understood, MLE predictions of a logit model
can directly be used as to estimates of the propensity score.
I already considered the twang package and the
2009 Aug 31
1
how to add data to some ts
Dear all,
Finally, I made it, my RPostgreSQL works. After working through some
tutorials, i was able to plot, get and replace several timeseries.
Still I miss the opportunity (syntax) to add data. Most tutorials are
about: "Download some S&P data from Yahoo and play around a little".
What I want to do is, add data to an existing timeseries. Is there a
possibility to add data
2008 Oct 09
1
adjusted t-test with unequal variance
Hi all,
right now i am simply comparing means. obviously this can be done by
the simple t.test respectively the welch test, if var.equal is set to
FALSE.
just like this
t.test( Y ~ group)
t.test( Y ~ group, var.equal = FALSE)
now that i need to compare weighted means i am using the lm function
as an adjusted t-test:
like
lmtest <- ( Y ~ group )
anova(lmtest)
2010 Jul 22
2
Sweave special characters problem
Dear all,
I use Sweave to create my reports. Unfortunately my script crashes whenever I my R code contains special characters like umlauts.
Is there a way to to escape special characters in Sweave... This is the line that crashes Sweave:
gl_bybranch = ddply(new_wans,.(period,Branchen), function(X) data.frame(Gesch?ftslage=mean(X$sentiment)))
Unfortunately I can't just rename it, because I
2010 May 06
1
how to get components / factors in factanal / princomp not loadings
Dear all,
i wonder if there?s a command to obtain the actual values of a principal component or a factor (not as.factor, but factanal) .
test=princomp(USArrests, cor = TRUE)
summary(test)
just outputs, standard deviation, Prop of Variance and cumulative proportion of variance.
test$loadings offers yet another proportion of variance scheme. why is that?
Apart from that:
Is there a
2009 Dec 14
1
lapply , mapply questions
Dear all,
i have a programming problem that should be simple, though i am stuck with it. Please note that this is not a specific geonames problem, though i use it as an example - it´s just a basic problem with lapply.
I use the geonames webservices with the R geonames packages which works almost smoothly.
I have a vector of Zipcodes and i want to do a geonames lookup for all of them, which