Displaying 20 results from an estimated 500 matches similar to: "Time Series Issues, Stationarity .."
2007 Dec 04
1
Best forecasting methods with Time Series ?
Hello,
In order to do a future forecast based on my past Time Series data sets
(salespricesproduct1, salespricesproduct2, etc..), I used arima() functions
with different parameter combinations which give the smallest AIC. I also
used auto.arima() which finds the parameters with the smallest AICs. But
unfortuanetly I could not get satisfactory forecast() results, even
sometimes catastrophic
2003 Apr 17
2
Testing for Stationarity of time series
Hi there,
Does anyone know if R has a function for testing whether a time series is
stationary??
Thanks in advance,
Wayne
Dr Wayne R. Jones
Statistician / Research Analyst
KSS Group plc
St James's Buildings
79 Oxford Street
Manchester M1 6SS
Tel: +44(0)161 609 4084
Mob: +44(0)7810 523 713
KSS Ltd
A division of Knowledge Support Systems Group plc
Seventh Floor St James's
2010 Apr 11
1
Statistical test for stationarity-how
How to find out if EURGBP is stationary?
Post the R codes for the same.
2009 May 20
1
stationarity tests
How can I make sure the residual signal, after subtracting the trend extracted through some technique, is actually trend-free ?
I would greatly appreciate any suggestion about some Stationarity tests.
I'd like to make sure I have got the difference between ACF and PACF right.
In the following I am citing some definitions. I would appreciate your thoughts.
ACF(k) estimates the correlation
2012 Feb 10
6
Importing a CSV file
I have been trying to import a csv file to r. but I get the same message everytime. the message is
Error in file(file, "rt") : cannot open the connection
In addition: Warning message:
In file(file, "rt") :
cannot open file 'Users:/sezginozcan/Downloads/beer.data.csv': No such file or directory
I use mac.
I tried this command also
2008 May 29
7
How do you exit a function in R?
For example, based on a certain condition, I may want to exit my code early:
# Are there the same number of assets in "prices" and
"positions"?
if (nAssetPositions != nAssetPrices) {
cat("Different number of assets! \n\n")
<exit function>
}
I have searched, but not
2009 Oct 30
1
how to test for stationarity in time series?
Hi all,
Could anybody tell me how to test for stationarity in time series?
Thanks a lot!
[[alternative HTML version deleted]]
2008 Jan 21
4
Stationarity of a Time Series
Does anyone know of a test for stationarity of a time series, or like
all ordination techniques it is a qualitative assessment of a
quantitative result. Books, papers, etc. suggestions welcome.
thanks
Stephen
--
Let's not spend our time and resources thinking about things that are
so little or so large that all they really do for us is puff us up and
make us feel like gods. We are
2004 Sep 04
1
tests for non-stationarity
Dear R list members,
Please excuse my ignorance but as a new comer to R I was wondering if anyone knows of any functions in R or Splus that can test a time-series for non-stationarity such as the Pettitt or the Mann-Kendall tests.
Kind regards,
Jon Nott
[[alternative HTML version deleted]]
2008 Mar 07
3
R-Logo in \LaTeX (Mag. Ferri Leberl)
Dear Mag. Ferri Leberl,
I'm using something like:
----------------------- tex.tex ---------------------------
\documentclass{article}
\usepackage{graphicx}
\usepackage{fancyvrb}
\newcommand{\Rlogo}{\protect\includegraphics[height=1.8ex,keepaspectratio]{Rlogo.pdf}}
\newcommand{\myinput}[1] {\begin{scriptsize}
\VerbatimInput[frame=single,label=#1]{#1}
\end{scriptsize}}
\title{The R logo,
2008 Mar 07
3
R-Logo in \LaTeX (Mag. Ferri Leberl)
Dear Mag. Ferri Leberl,
I'm using something like:
----------------------- tex.tex ---------------------------
\documentclass{article}
\usepackage{graphicx}
\usepackage{fancyvrb}
\newcommand{\Rlogo}{\protect\includegraphics[height=1.8ex,keepaspectratio]{Rlogo.pdf}}
\newcommand{\myinput}[1] {\begin{scriptsize}
\VerbatimInput[frame=single,label=#1]{#1}
\end{scriptsize}}
\title{The R logo,
2006 Jul 06
2
KPSS test
Hi,
Am I interpreting the results properly? Are my conclusions correct?
> KPSS.test(df)
---- ----
KPSS test
---- ----
Null hypotheses: Level stationarity and stationarity around a linear trend.
Alternative hypothesis: Unit root.
----
Statistic for the null hypothesis of
level stationarity: 1.089
Critical values:
0.10 0.05 0.025 0.01
0.347 0.463
2009 Jun 15
3
Assigning Data a name from within another variable?
Hi All,
I have hunted high and low and tried dozens of things but have yet to
achieve the result I require. Below is my code (taken mostly from another
thread on here) thus far:
files<-list.files()
files<-files[grep('.wm4', files)]
labels<-gsub('.wm4', '',files)
for(i in 1:length(files)){
X<-read.table(files[i])
<My problem is here!>
What I am trying
2007 Dec 08
2
time series tests
Hi all,
Can anyone clear my doubts about what conclusions to take with the following what puts of some time series tests:
> adf.test(melbmax)
Augmented Dickey-Fuller Test
data: melbmax
Dickey-Fuller = -5.4075, Lag order = 15, p-value = 0.01
alternative hypothesis: stationary
Warning message:
p-value smaller than printed p-value in: adf.test(melbmax)
2008 Jun 26
1
stationary "terminology" time series question
This is not exactly an R question but the R code below may make my
question more understandable.
If one plots sin(x) where x runs from -pi to pi , then the curve hovers
around zero obviously. so , in a"stationary in the mean" sense,
the series is stationary. But, clearly if one plots the acf, the
autocorrelations at lower lags are quite high and, in the "box jenkins"
2005 May 02
1
Trying to understand kpss.test() in tseries package
I'm trying to understand how to use kpss.test() properly. If I have a
level stationary series like rnorm() in the help page, shouldn't I get a
small p-value with the null hypothesis set to "Trend"? The (condensed)
output from kpss.test() for the two possible null hypotheses is given
below. I don't see any significant difference between these results.
> x <-
2005 Mar 08
2
The null hypothesis in kpss test (kpss.test())
is that 'x' is level or trend stationary. I did this
> s<-rnorm(1000)
> kpss.test(s)
KPSS Test for Level Stationarity
data: s
KPSS Level = 0.0429, Truncation lag parameter = 7,
p-value = 0.1
Warning message:
p-value greater than printed p-value in:
kpss.test(s)
My question is whether p=0.1 is a good number to
reject
N0? On the other hand, I have a
2007 Aug 16
2
ADF test
Hi all,
Hope you people do not feel irritated for repeatedly sending mail on Time series.
Here I got another problem on the same, and hope I would get some answer from you.
I have following dataset:
data[,1]
[1] 4.96 4.95 4.96 4.96 4.97 4.97 4.97 4.97 4.97 4.98 4.98 4.98 4.98 4.98 4.99 4.99 5.00 5.01
[19] 5.01 5.00 5.01 5.01 5.01 5.01 5.02 5.01 5.02 5.02 5.03 5.03 5.03
2005 Sep 21
2
Result Documents XML or JSON?
My Java servlets can generate both JavaScript objects, like
JSON, and XML. I can generate both pretty easily.
What''s best practice for AJAX responses? Return scripts to be
evaled by the Ajax control, or return XML documents and iterate
them using XML DOM?
Thanks.
--
Alan Gutierrez - alan@engrm.com
- http://engrm.com/blogometer/index.html
-
2010 Jan 24
1
auto reading in multiple txt files with filename as 1st column "ID"
Hi,
I have many .txt files which look like this:
2009/02/07 12:30:10.0 ? ? ?5.0161 ? ? ?13.208
2009/02/07 12:45:10.0 ? ? ?5.0102 ? ? ?13.350
2009/02/07 13:00:10.0 ? ? ?5.0044 ? ? ?13.473
....
....
....
2009/02/07 16:30:10.0 ? ? ?4.9366 ? ? ?13.788
2009/02/07 16:45:10.0 ? ? ?4.9397 ? ? ?13.798
end data.
###I can read in all files from "my_folder" using the following code: