Displaying 16 results from an estimated 16 matches similar to: "question reg. conditional regression"
2009 Jun 19
1
(FULL) Need help to optimize a piece of code involving zoo objects
(Sorry, sent the message before I finished it)
Hello, everyone
I have a long script that uses zoo objects. In this script I used
simple moving averages and these I can very efficiently calculate with
filter() functions.
Now, I have to use special "exponential" moving averages, and the only
way I could write the code was with a for-loop, which makes everything
extremely slow.
I don't
2009 Jun 19
1
Need help to optimize a piece of code involving zoo objects
Hello, everyone
I have a long script that uses zoo objects. In this script I used
simple moving averages and these I can very efficiently calculate with
filter() functions.
Now, I have to use special "exponential" moving averages, and the only
way I could write the code was with a for-loop, which makes everything
extremely slow.
I don't know how to optimize the code, but I need to
2005 Jul 08
1
help with ARIMA and predict
I'm trying to do the following out of sample
regression with autoregressive terms and additional x
variables:
y(t+1)=const+B(L)*y(t)+C(1)*x_1(t)...+C(K)*x_K(t)
where:
B(L) = lag polynom. for AR terms
C(1..K) = are the coeffs. on K exogenous variables
that have only 1 lag
Question 1:
-----------
Suppose I use arima to fit the model:
2010 Oct 02
1
problem with spline
I am trying to interpolate missing values using spline and am running
into some strange problems.
first, this works just fine:
x<- c(1:10, rep(NA, 3), 14:20)
y<- c(rnorm(10), rep(NA,3), rnorm(7))
s<- spline(x,y, n=length(x))
plot(x,y)
lines(s, col="blue")
but look at what happens with my real data (sorry for the long vectors here):
x<- c(-9.816, -9.801, -9.801, -9.795,
2010 Oct 02
0
Running R on Amazon EC2 : Public Snapshot for use
Dear All,
I ave created a public snapshot for use on Amazon EC2 using 64 bit Windows.
If you want to try R on multiple cores ,remote desktop you can use this
snapshot to create copies.
It has R, GUIs for beginners (like RCommander , Deducer- Alas rattle failed
due to RGtk+) and a lot of R analytical packages.
It also has Chrome for browsing, Adobe Reader for reading help, and a
dataset WDI (in
2008 Nov 05
1
Problems computing 2-way-mixed-model ANOVA
Dear Experts,
I am new to R and unfortunately cannot start with a simply statistical
analysis:
I manually determined the volume of the right and left hippocampus in
a group of meditators and in a group of controls. My data-sheet looks
as follows:
observation subject group age gender hemisphere volume
1 am04 m 25 f left 3.637
2 am04 m 25 f right 3.713
3 ao08 m 47 m left 3.715
4 ao08 m 47
2013 Apr 11
2
Read the data from a text file and reshape the data
I have a data set for different time intervals. The data has three comment
lines before data for each time interval. For each time interval there are
500 data points. I want to change the dataset such that I have the following
format:
t1 t2 t3 ................
0.00208 0.00417 0.00625 .................
a1 a2 a3 ...................
2012 Dec 08
4
read.table()
Hi List,
I have spent more than 30 minutes, but failed to read in this file using the read.table() function. I could not figure out how to fix the following error.
Error in scan(file, what, nmax, sep, dec, quote, skip, nlines, na.strings, : line 1 did not have 6 elements
Any help would be be appreciated.
Thanks,
Pradip Muhuri
####### below is the reproducible example
xd1 <-
2014 Sep 01
1
Correlation Matrix with a Covariate
R Help -
I'm trying to run a correlation matrix with a covariate of "age" and will
at some point will also want to covary other variables concurrently.
I'm using the "psych" package and have tried other methods such as writing
a loop to extract semi-partial correlations, but it does not seem to be
working. How can I accomplish this?
library(psych)
> set.cor(y =
2006 May 24
2
data.frame
Dear all,
Does any one knows why should I get the following error message, when trying
to do a simple data.frame??
DataF<-data.frame(Subject,BiomR,Spp,Capas,Litter,Herbs,LitterD,MaxCanH,DDifS
p,DSSp,Slope, CanDens,NearestSp)
Erro em data.frame(Subject, BiomR, Spp, Capas, Litter, Herbs, LitterD, :
arguments imply differing number of rows: 202, 0
The data I am using
2006 Apr 06
1
How to implement an iterative unit root test
Hello,
How can an interative unit root test be implemented in R?
More specifically, given a time series, I wish to perform the Dickey
Fuller Test on a daily basis for say the last 100 observations. It would
be interative in the sense that this test would be repeated each day for
the last 100 observations.
Given the daily Dickey Fuller estimates of delta for the autoregressive
process
d(Y(t))
2012 Apr 26
2
HoltWinters() fitted values
Hi everyone,
I'm using the HoltWinters() function to do a time series analysis. The
function only returns the back fitted values ($fitted) after the first year
of data, which is my case, is a little more than half. However, when I use
the plot() function, it plots the back fit for almost the entire data set.
Any ideas on how to extract the fitted values going all the way back to the
start
2006 Apr 15
2
manual construction of box&whisker plot
Dear useRs,
how can I construct a box&whisker plot based on the vector "fivenum"?
The challenge I face is as follow: I have a table such as
x | fivenum
---------------
... | (.....)
... | (.....)
and so forth....
For each observation x I have generated a vector containing the fivenum
estimates.
The first challenge is to group my fivenum vectors into groups based on
a
2013 Feb 28
2
What can I do to UNDERSTAND why I can't reach centos.org (but everyone else can)?
What can I do to UNDERSTAND why, periodically, I can't reach
www.centos.org (but everyone else can)?
Every few months, http://www.centos.org just drops off for me
and for me only. It's not the web site, because I can reach it
via a proxy (e.g., TOR browser bundle) and other tests show it
to be alive (e.g., http://www.downforeveryoneorjustme.com/centos.org
or
2012 May 04
7
Breaking up a Row in R (transpose)
I have the following:
Time A1 A1 B1 B1 C1 C2
x y x y x y
0 5 6 6 7 7 9
1 3 4 4 3 9 9
2 5 2 6 4 7 4
I want to change it to the following:
0 1 2
x y x y x y
A1 5 6 3 4 5 2
B1
2007 Dec 21
1
post hoc in repeated measures of anova
Hallo, I have this dataset with repeated measures. There are two
within-subject factors, "formant" (2 levels: 1 and 2) and "f2 Ref" (25
levels: 670, 729, 788, 846, 905, 1080, 1100, 1120, 1140, 1170, 1480,
1470, 1450, 1440, 1430, 1890, 1840, 1790, 1740, 1690, 2290, 2210,
2120, 2040, 1950), and one between-subject factor, lang (2 levels:1
and 2). The response variable