Displaying 20 results from an estimated 2000 matches similar to: "question about 3-d plot"
2010 May 06
1
question about rolling regressions
Hi All,
I am using R 2.11.0 on a Ubuntu machine. I have a time series data set and
want to run rolling regressions with it. Any suggestions would be useful.
Here are the details:
(1) I convert relevant variables into time series objects and compute first
differences:
vad <- ts(data$ALLGVA/data$GDPDEF, start=1948, frequency=1)
emp <- ts(data$ALLEMP, start=1948, frequency=1)
vad.dif1 <-
2010 May 02
1
question about 2SLS
Hi All,
I am using R 2.11.0 on a Ubuntu machine. I estimated a model using "tsls"
from the package "sem". Is there a way to get Newey West standard errors for
the parameter estimates?
When estimating the model by OLS, I used "NeweyWest" from the package
"sandwich" to get HAC standard errors. But, I am not able to use the same
method with the results of the
2009 Mar 03
4
scatter plot question
Hi R Users,
I have a dataframe like this:
id x rho
A 1 0.1
B 20 0.5
C 2 0.9
...
I want to do a scatter plot of "x" versus "rho" but for each point on the
scatter plot I want the corresponding entry for "id" instead of points. In
STATA I can do so by
twoway (scatter x rho, mlabel(id))
How can I do the same in R? I am sure there is some simple way to do
2007 Oct 24
3
how to loop over a group of variables?
Hi All,
I have a data frame with a group of variables named b1, b2, b3, ..., b18. These variables take the value 1, 2 or NA. For each observation, I want to do some computation by looping over the values for the group of variables: b1 to b18. In STATA I would do:
forval i=1/18 {
--- use b`i' for computation ----
}
How can this be done in R?
Deepankar
2008 May 10
3
question about subseting a dataframe
Hi!
I am using R version 2.7.0 and am working on a panel dataset read into R as
a dataframe; I call it "ex". The variables in "ex" are: id year x
id: a character string which identifies the unit
year: identifies the time period
x: the variable of interest (which might contain NAs).
Here is an example:
> id <- rep(c("A","B","C"),2)
>
2006 Dec 19
4
Upgrading
Hi!
As per Thomas' advice, I upgraded R by using "update.packages()" and got the following warning messages:
Warning messages:
1: installation of package 'lmtest' had non-zero exit status in: install.packages(update[, "Package"], instlib, contriburl = contriburl,
2: installation of package 'quadprog' had non-zero exit status in: install.packages(update[,
2007 Apr 23
4
Estimates at each iteration of optim()?
I am trying to maximise a complicated loglikelihood function with the "optim" command. Is there some way to get to know the estiamtes at each iteration? When I put "control=list(trace=TRUE)" as an option in "optim", I just got the initial and final values of the loglikelihood, number of iterations and whether the routine has converged or not. I need to know the
2007 Nov 06
4
C++ and R interface
Hi All,
I am trying to do an ML estimation in R. My likelihood function has
several nested loops and so it takes a lot of time (days when I use the
genetic algorithm for optimization) for the optimization to finish.
Unable to avoid loops, I am thinking of writing the likelihood function
in C++ and calling it from within R when using *optim()*. I found that
one can call C functions (once they have
2010 Jan 30
2
question about time series objects
Hi All,
I have a very simple question about a time series object: how to access
values for a particular year and quarter (say)?
Suppose, following
http://www.stat.pitt.edu/stoffer/tsa2/R_time_series_quick_fix.htm
I have read in data as a time series; here is how it looks.
* Qtr1 Qtr2 Qtr3 Qtr4
1960 0.71 0.63 0.85 0.44
1961 0.61 0.69 0.92 0.55
. . . . .
2007 Apr 19
3
Problem installing packages
I tried to install the package "tseries" but could not do so. Any
suggestions are welcome. I am using Ubuntu Linux and here is what I did:
$ sudo R
Then once in R, I did
> install.packages("tseries", dep=TRUE)
which gave a long list of errors. Going through them, I saw that the
basic problem was that the package "grid" was not found by the packages
(like
2007 Apr 18
3
Problems in programming a simple likelihood
As part of carrying out a complicated maximum likelihood estimation, I
am trying to learn to program likelihoods in R. I started with a simple
probit model but am unable to get the code to work. Any help or
suggestions are most welcome. I give my code below:
************************************
mlogl <- function(mu, y, X) {
n <- nrow(X)
zeta <- X%*%mu
llik <- 0
for (i in 1:n) {
if
2024 Jan 11
4
arrow on contour line
Hello,
I am drawing contour lines for a function of 2 variables at one level of
the value of the function and want to include a small arrow in any
direction of increase of the function. Is there some way to do that?
Below is an example that creates the contour lines. How do I add one small
arrow on each line in the direction of increase of the function (at some
central point of the contour
2002 Aug 12
1
question about cloud() in lattice package
Hi all,
I have been previously been using scatterplot3d package to create some graphs but unfortunately it does not allow me to rotate the
plot on all three axis. The cloud() function in the lattice package does allow me to do so. When I was using scatterplot3d I was
using a script (Shown Below) to calculate the mean, quartiles and range limits for all three axis and I was representing that on the
2006 Jul 18
2
FW: Large datasets in R
Hi,
I have two further comments/questions about large datasets in R.
1. Does R's ability to handle large datasets depend on the operating
system's use of virtual memory? In theory, at least, VM should make the
difference between installed RAM and virtual memory on a hard drive
primarily a determinant of how fast R will calculate rather than whether or
not it can do the calculations.
2006 Dec 19
2
attach and object masking
Hi R users!
I am new to R. When I try to attach a simple dataset using the attach() command, I get the following message:
> attach(data1)
The following object(s) are masked from package:base :
write
Can someone tell me what this means? (`write' is the name of a variable in the dataset). And, do I need to do do something about this.
Thanks.
2007 Oct 26
1
finding birth position
Hi All,
I have data on the sequence of births for families with completed
fertility cycle (in a data frame); the relevant variables are called b1,
b2, b3, b4, b5, b6 and record the birth of the first, second, ..., sixth
child. So,
b1=1 if the first birth is male,
b1=2 if the first birth is female,
and b1=NA if the family did not record any first birth.
Similarly for b2, b3, b4, b5 and b6.
I
2007 May 24
3
Problem with numerical integration and optimization with BFGS
Hi R users,
I have a couple of questions about some problems that I am facing with
regard to numerical integration and optimization of likelihood
functions. Let me provide a little background information: I am trying
to do maximum likelihood estimation of an econometric model that I have
developed recently. I estimate the parameters of the model using the
monthly US unemployment rate series
2007 Dec 02
1
speeding up likelihood computation
R Users:
I am trying to estimate a model of fertility behaviour using birth history data with maximum likelihood. My code works but is extremely slow (because of several for loops and my programming inefficiencies); when I use the genetic algorithm to optimize the likelihood function, it takes several days to complete (on a machine with Intel Core 2 processor [2.66GHz] and 2.99 GB RAM). Computing
2007 Oct 25
2
the difference between temp and .temp
Hi everyone -
This came up within the last day -- Jim's response to Deepankar is pasted below.
There are probably lots of reasons, but what is the advantage to using
.temp over, say, temp?
I often find myself writing temporary objects -- should I use the .
preface? What would be the advantages to doing so?
Thanks in advance for what will surely be a collection of illuminating
responses.
2006 Sep 12
1
lattice cloud and conditional axis limits
I'm using the 'cloud' function in the 'lattice' package to produce
multi-panel 3D scatter plots. The range of the values used vary much
between each panel (especially on the z axis), so I wish the axis limits
to be calculated based on the (conditional) data.
Here's a minimal example:
library(lattice)
z=1:200
x=runif(200)
y=runif(200)
s=factor(rep(c(1,2),each=100))