Displaying 20 results from an estimated 1000 matches similar to: "Eliminate cases in a subset of a dataframe"
2012 May 29
2
setting parameters equal in lm
Forgive me if this is a trivial question, but I couldn't find it an answer
in former forums. I'm trying to reproduce some SAS results where they set
two parameters equal. For example:
y = b1X1 + b2X2 + b1X3
Notice that the variables X1 and X3 both have the same slope and the
intercept has been removed. How do I get an estimate of this regression
model? I know how to remove the intercept
2011 Oct 18
1
cygwing warming when creating a package in windows
Dear All,
I am a beginner creating R packages. I followed the Leisch (2009) tutorial
and the document ?Writing R Extensions? to write an example.
I installed R 2.12.2 (I also tried R2.13.2), the last version of Rtools and
the recommended packages in a PC with Windows 7 Home Premium.
I can run R CMD INSTALL linmod in the command prompt and the R CMD check
linmod. The following outputs are
2013 Mar 12
1
Cook's distance
Dear useRs,
I have some trouble with the calculation of Cook's distance in R.
The formula for Cook's distance can be found for example here:
http://en.wikipedia.org/wiki/Cook%27s_distance
I tried to apply it in R:
> y <- (1:400)^2
> x <- 1:100
> lm(y~x) -> linmod # just for the sake of a simple example
>
2024 May 15
2
Extracting values from Surv function in survival package
OS X
R 4.3.3
Colleagues
I have created objects using the Surv function in the survival package:
> FIT.1
Call: survfit(formula = FORMULA1)
n events median 0.95LCL 0.95UCL
SUBDATA$ARM=1, SUBDATA[, EXP.STRAT]=0 18 13 345 156 NA
SUBDATA$ARM=2, SUBDATA[, EXP.STRAT]=1 13 5 NA 186 NA
SUBDATA$ARM=2, SUBDATA[, EXP.STRAT]=2 5
2024 May 16
1
Extracting values from Surv function in survival package
Hi Dennis,
look at the help page for summary.survfit, the Value n.event.
G?ran
On 2024-05-15 22:41, Dennis Fisher wrote:
> OS X
> R 4.3.3
>
> Colleagues
>
> I have created objects using the Surv function in the survival package:
>> FIT.1
> Call: survfit(formula = FORMULA1)
>
> n events median 0.95LCL 0.95UCL
>
2009 Oct 26
2
What is the most efficient practice to develop an R package?
I am reading Section 5 and 6 of
http://cran.r-project.org/doc/contrib/Leisch-CreatingPackages.pdf
It seems that I have to do the following two steps in order to make an
R package. But when I am testing these package, these two steps will
run many times, which may take a lot of time. So when I still develop
the package, shall I always source('linmod.R') to test it. Once the
code in
2010 Apr 27
3
Problem calculating multiple regressions on a data frame.
Hi there,
I am stuck trying to solve what should be a fairly easy problem.
I have a data frame that essentially consists of (ID, time as seqMonth,
variable, value) and i want to find the regression coefficient of value vs
time for each combination of ID and Variable.
I have tried several approaches and none of them seems to work as i
expected.
For example, i have tried:
2006 Jan 11
1
updating formula inside function
Dear R-Helpers
Given a function like
foo <- function(data,var1,var2,var3) {
f <- formula(paste(var1,'~',paste(var2,var3,sep='+'),sep=''))
linmod <- lm(f)
return(linmod)
}
By typing
foo(mydata,'a','b','c')
I get the result of the linear model a~b+c.
How can I rewrite the function so that the formula can be updated inside
the function,
2007 Aug 01
1
Problem to remove loops in a routine
Dear R-users,
I have written the following code to generate some trellis plots. It
works perfectly fine except that it is quite slow when it is apply to my
typical datasets (over several thousands of lines). I believe the
problem comes from the loops I am using to subset my data.frame. I read
in the archives that the tapply function is often more efficient than a
loop in R. Unfortunately ,
2010 Jun 18
1
How to calculate the robust standard error of the dependent variable
Hi, folks
linmod=y~x+z
summary(linmod)
The summary of linmod shows the standard error of the coefficients. How can
we get the sd of y and the robust standard errors in R?
Thanks!
[[alternative HTML version deleted]]
2010 Jun 21
2
How to predict the mean and variance of the dependent variable after regression
Hi, folks,
As seen in the following codes:
x1=rlnorm(10)
x2=rlnorm(10,mean=2)
y=rlnorm(10,mean=10)### Fake dataset
linmod=lm(log(y)~log(x1)+log(x2))
After the regression, I would like to know the mean of y. Since log(y) is
normal and y is lognormal, I need to know the mean and variance of log(y)
first. I tried mean (y) and mean(linmod), but either one is what I want.
Any tips?
Thanks in
2011 Aug 17
3
How to apply a function to subsets of a data frame *and* obtain a data frame again?
Dear all,
First, let's create some data to play around:
set.seed(1)
(df <- data.frame(Group=rep(c("Group1","Group2","Group3"), each=10),
Value=c(rexp(10, 1), rexp(10, 4), rexp(10, 10)))[sample(1:30,30),])
## Now we need the empirical distribution function:
edf <- function(x) ecdf(x)(x) # empirical distribution function evaluated at x
##
2003 Mar 25
2
Help with data.frame subsets
Hello all,
I'm trying to get a subset of a data frame by taking all rows where the 2nd
column is >= Min and <= Max. I can do that by a 2 step process similar to
the following:
subData <- dataFrame[dataFrame[,2] >= Min,]
subData2 <- subData[subData[,2] <= Max,]
Then I try to graph the results where col 2 is the X var and col 3 is the Y
var. Therefore I do the following:
X
2011 Oct 31
1
googleVis motionchart - slow with Date class
Hi,
I am trying to create a googleVis motion chart with monthly data. When formatting the date column as a Date class variable, the plot as presented in the browser becomes considerably slower and very prone to crashing the browser. To illustrate this issue I have modified the WorldBank demo.
### objects from demo("WorldBank", package = "googleVis")
M <-
2007 Oct 01
3
mean of subset of rows
Dear list,
this must be an easy one:
I have a data.frame of two columns, "ID" with four different levels (A
to D) and numerical "size", and each of the 4 different IDs is
repeated a
different number of times. I would like to get the mean size for each
ID as another data.frame. I have tried the following:
>ID= as.character(unique(data[,1])) # I use unique() because
2008 Mar 10
3
Weighting data when running regressions
Dear R-Help,
I'm new to R and struggling with weighting data when I run regression. I've
tried to use search to solve my problem but haven't found anything helpful
so far.
I (successfully) import data from SPSS (15) and try to run a linear
regression on a subset of my data file where WEIGHT is the name of my
weighting variable (numeric), e.g.:
library(foreign)
2008 Jun 19
2
Advanced Filtering problem
http://www.nabble.com/file/p18018170/subdata.csv subdata.csv
I've attached 100 rows of a data frame I am working with.
I have one factor, id, with 27 levels. There are two columns of reference
data, x and y (UTM coordinates), one column "date" in POSIXct format, and
one column "diff" in times format (chron package).
What I am trying to do is as follows:
For each day
2007 Jun 21
2
Overlaying lattice graphs (continued)
Dear R Users,
I recently posted an email on this list about the use of data.frame and
overlaying multiple plots. Deepayan kindly indicated to me the
panel.superposition command which worked perfectly in the context of the
example I gave.
I'd like to go a little bit further on this topic using a more complex
dataset structure (actually the one I want to work on).
>mydata
Plot
2011 Mar 27
1
Sweave: include a multi-page-pdf plot
Hi,
I'm just starting out with Sweave, and I can't get a plot(linmod) to
display all four plots:
<< bild >>=
x1 <- runif(100)
x2 <- rexp(100)
y <- 3 + 4*x1 + 5*x2 + rnorm(100)
mod <- lm(y~x1+x2)
plot(mod)
@
Some Text
<<fig=TRUE>>=
<<bild>>
@
This plots only the first image of the four-page plot.lm() result.
I don't want to use
2012 Sep 24
0
stop on rows where !is.na(mydata$ti_all)
Dear R experts,
I got help to build a loop but there is a bug inside it that causes
one part of the mechanism to fail.
It should grow once, but if keep growing on rows where $ti_all is not NA.
Here is a wall of code that very crudely demonstrates the problem,
there is a couple of dim() outputs at the end where you can see how it
the second time around keeps adds (2) rows, but this does not