Displaying 20 results from an estimated 200 matches similar to: "Problem with Stationary Bootstrap"
2009 Apr 23
2
Two 3D cones in one graph
Dear R-users:
The following code produces two cones in two panels. What I would like
to have is to have them in one, and to meet in the origin. Does anyone
have any good ideas how to do this?
Thanks for your help
Jaakko
library(lattice)
A<-matrix(ncol=2, nrow=64)
for(i in 0:63)
{
A[i+1,1]<-sin(i/10)
A[i+1,2]<-cos(i/10)
}
2012 Feb 08
1
Fitting polynomial (power greater than 2)
Hey all, first time poster here. I'm new to R and working on my first real
programming and forecasting asignment. I'm using unemployment data from
1948-2012. I successfully completed part a and the linear fit for part b,
but i am really struggling fitting a polynomial with a power greater than 2
to my forecast. I'll upload my R code at the bottom. Any help is very much
appreciated!
2007 Jul 12
2
lead
Hi,
is there any function in R that shifts elements of a vector to the
opposite direction of what Lag() of the Hmisc package does? (something
like, Lag(x, shift = -1) )
Thanks
Zava
--------------------------------------------------------
This is not an offer (or solicitation of an offer) to buy/se...{{dropped}}
2011 Aug 04
2
Efficient way of creating a shifted (lagged) variable?
Hello!
I have a data set:
set.seed(123)
y<-data.frame(week=seq(as.Date("2010-01-03"), as.Date("2011-01-31"),by="week"))
y$var1<-c(1,2,3,round(rnorm(54),1))
y$var2<-c(10,20,30,round(rnorm(54),1))
# All I need is to create lagged variables for var1 and var2. I looked
around a bit and found several ways of doing it. They all seem quite
complicated - while in
2001 Aug 30
1
MCMC coding problem
Dear All,
I am trying to convert some S-plus code that I have to run MCMC into
R-code. The program works in S-plus, but runs slowly.
I have managed to source the program into R. R recognizes that the program
is there; for example, it will display the code when I type the function
name at the prompt. However, the program will not run. When I try to run
the program, I get the following error
2006 Jan 19
2
Tobit estimation?
Folks,
Based on
http://www.biostat.wustl.edu/archives/html/s-news/1999-06/msg00125.html
I thought I should experiment with using survreg() to estimate tobit
models.
I start by simulating a data frame with 100 observations from a tobit model
> x1 <- runif(100)
> x2 <- runif(100)*3
> ystar <- 2 + 3*x1 - 4*x2 + rnorm(100)*2
> y <- ystar
> censored <- ystar <= 0
2012 Oct 25
2
How to extract auc, specificity and sensitivity
I am running my code in a loop and it does not work but when I run it
outside the loop I get the values I want.
n <- 1000; # Sample size
fitglm <- function(sigma,tau){
x <- rnorm(n,0,sigma)
intercept <- 0
beta <- 0
ystar <- intercept+beta*x
z <- rbinom(n,1,plogis(ystar))
xerr <- x + rnorm(n,0,tau)
model<-glm(z ~ xerr, family=binomial(logit))
2007 Oct 31
1
Simple Umacs example help..
Hello all...
I am just starting to teach myself Bayesian methods, and am
interested in learning how to use UMacs. I've read the
documentation, but the single example is a bit over my head at the
level I am at right now. I was wondering if anyone has any simple
examples they'd like to share. I've successfully done a couple of
simple gibbs examples, but have had a hard time
1999 Dec 09
1
tsboot
Fritz,
I have slightly adapted (didn't work before) "tsboot" from the "boot"
library to the current time series conventions of R. The following patch
will do that. I suggest to apply this patch to the file
"boot/R/bootfuns.q" of the "boot" library at CRAN.
best
Adrian
--- bootfuns.orig.q Thu Dec 9 10:07:23 1999
+++ bootfuns.q Thu Dec 9 10:06:51 1999
1999 Dec 09
1
tsboot
Fritz,
I have slightly adapted (didn't work before) "tsboot" from the "boot"
library to the current time series conventions of R. The following patch
will do that. I suggest to apply this patch to the file
"boot/R/bootfuns.q" of the "boot" library at CRAN.
best
Adrian
--- bootfuns.orig.q Thu Dec 9 10:07:23 1999
+++ bootfuns.q Thu Dec 9 10:06:51 1999
2012 Oct 20
1
Logistic regression/Cut point? predict ??
I am new to R and I am trying to do a monte carlo simulation where I
generate data and interject error then test various cut points; however, my
output was garbage (at x equal zero, I did not get .50)
I am basically testing the performance of classifiers.
Here is the code:
n <- 1000; # Sample size
fitglm <- function(sigma,tau){
x <- rnorm(n,0,sigma)
intercept <- 0
beta
2009 Jul 17
6
Solving two nonlinear equations with two knowns
Dear R users,
I have two nonlinear equations, f1(x1,x2)=0 and f2(x1,x2)=0. I try to use optim command by minimize f1^2+f2^2 to find x1 and x2. I found the optimal solution changes when I change initial values. How to solve this?
BTW, I also try to use grid searching. But I have no information on ranges of x1 and x2, respectively.
Any suggestion to solve this question?
Thanks,
Kate
2010 Mar 01
1
p-values from bootstrapping of time series (tsboot)
Does anyone know how p-values can be generated if tsboot (stationary
bootstrap) for time series is performed?
That would be of great help. Thanks a lot for your comments.
Markus
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2003 Apr 11
1
smb client file list
Hello,
Am new to this list so pardon if this question has been asked before.
I am trying to find a way to access MS "net shares" and be able to execute
"net use" without installing MS. I am looking at a floppy-based linux+samba
solution. Most of the floppy linux contain apps I don't need or are
centered more towards a router. So I now plan to create my own bootable
2008 Dec 16
1
Prediction intervals for zero inflated Poisson regression
Dear all,
I'm using zeroinfl() from the pscl-package for zero inflated Poisson
regression. I would like to calculate (aproximate) prediction intervals
for the fitted values. The package itself does not provide them. Can
this be calculated analyticaly? Or do I have to use bootstrap?
What I tried until now is to use bootstrap to estimate these intervals.
Any comments on the code are welcome.
2010 Mar 27
1
R runs in a usual way, but simulations are not performed
Dear addresses, I need perform a batch of 10 000 simulations for each of
4 options considered. (The idea is to obtain the parameter estimates in
a heteroskedastic linear regression model - with additive or mixed
heteroskedasticity - via the Kenward-Roger small-sample adjusted
covariance matrix of disturbances). For this purpose I wrote an R
program which would capture all possible options (true
2009 Sep 18
1
lapply - value changes as parameters to function?
Hi,
I'm trying to get better at things like lapply but it still stumps
me. I have a function I've written, tested and debugged using
individual calls to the function, ala:
ResultList5 = DoAvgCalcs(IndexData, Lookback=5,
SampleSize=TestSamples , Iterations=TestIterations )
ResultList8 = DoAvgCalcs(IndexData, Lookback=8,
SampleSize=TestSamples , Iterations=TestIterations )
ResultList13
2006 Feb 07
3
Dinamic controller
Is it possible to make a Rails app respond to a "dinamic" controller?
As I understand method_missing can be used inside a controller to
respond to nonexisting methods, is it possible to provide a similar
behavior at a controller level? I am not sure at whic level would this
code be inserted...
--
An?bal Rojas
http://www.lacaraoscura.com/
anibalrojas@gmail.com
2015 Apr 14
3
Independent dual monitors on CentOS 7
Does anyone have the magic incantation required to getting
*independent* multi-monitors going under CentOS 7? Ideally
under xfce or trinity, but I'm interested about GNOME/KDE
observations as well.
I'm trying to move my main workstation from CentOS5 to CentOS7
and while the spanned desktop works, not having independent
monitors really cuts into my productivity. i.e.: I couldn't
2009 Sep 09
3
lag a data.frame column?
Sometimes it's the simple things...
Why doesn't this lag X$x by 3 and place it in X$x1? (i.e. - Na's in
the first 3 rows and then values showing up...)
The help page does talk about time series. If lag doesn't work on
data.frame columns then what would be the right function to use to lag
by a variable amount?
Thanks,
Mark
X=data.frame(x=seq(1:10))
X$x1=lag(X$x, 3)
X