Displaying 20 results from an estimated 54 matches for "stationarity".
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 0.574 0.739
----
Statistic for the null hypothesis of
trend stationarity: 0.13...
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...
2006 Jul 06
1
Access values in kpssstat-class
Hi,
How can I access the Values stored in kpssstat-class given by KPSS.test function and store it in a variable.
For example:
>x <- rnorm(1000)
>test <- KPSS.test(ts(x))
>test
---- ----
KPSS test
---- ----
Null hypotheses: Level stationarity and stationarity around a linear trend.
Alternative hypothesis: Unit root.
----
Statistic for the null hypothesis of
level stationarity: 0.138
Critical values:
0.10 0.05 0.025 0.01
0.347 0.463 0.574 0.739
----
Statistic for the null hypothesis of
trend stationarity: 0.03...
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]]
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]]
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 between y(t) and y(t-k) like an ordinary correlation coefficient.
ACF is the simple ( i.e. unco...
2007 Dec 08
2
time series tests
...melbmax)
Box-Pierce test
data: melbmax
X-squared = 1893.093, df = 1, p-value < 2.2e-16
> Box.test(melbmax,type="Ljung-Box")
Box-Ljung test
data: melbmax
X-squared = 1894.650, df = 1, p-value < 2.2e-16
> kpss.test(melbmax)
KPSS Test for Level Stationarity
data: melbmax
KPSS Level = 0.1163, Truncation lag parameter = 13, p-value = 0.1
Warning message:
p-value greater than printed p-value in: kpss.test(melbmax)
> x=time(melbmax)
> y=as.vector(melbmax)
> melbmaxsaz=lowess(x,y,f=0.05)$y
> melbmaxtrend=lowess(x,y,f=0.5)$y
> melbmaxr...
2005 Mar 09
1
about kpss.test()
Hi All,
First of all, could you tell me what the "KPSS Level"
in the output of the test means?
I have a series, x, of periodic data and tried
kpss.test() on it to verify its stationarity. The
tests
gave me the p-value above 0.1. Since the null
hypothesis N0 is that the series _is_ stationary, this
means that I cannot reject N0. But the series does
look
periodic!
So does all this say stationarity and periodicity can
co-exist?
Thanks,
Weiguang
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
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 series r and did the
following:
> plot.ts(r)...
2008 Jun 26
1
stationary "terminology" time series question
...terms of its acf. so,
i'm confused in terms of what ithe statistical definition of stationary
is
as box jenkins define it ?
I don't have their text in front of me but I don't remember them having
an example such as below when they talk about needing to difference
series
to achieve stationarity. thanks for any insights or a text that talks
about this.
x <- seq(pi,-pi,by=-pi/4)
y <- sin(x)
plot(x,y)
acf(y)
P.S: this question arose because a colleague asked me to look at the
plot of his series and the associated acf and he claims it's a
stationary series and
I'm trying t...
2010 Apr 11
1
Statistical test for stationarity-how
How to find out if EURGBP is stationary?
Post the R codes for the same.
2007 Nov 26
3
Time Series Issues, Stationarity ..
Hello,
I am very new to R and Time Series. I need some help including R codes
about the following issues. I' ll really appreciate any number of
answers...
# I have a time series data composed of 24 values:
myinput = c(n1,n2...,n24);
# In order to make a forecasting a, I use the following codes
result1 = arima(ts(myinput),order = c(p,d,q),seasonal = list(order=c(P,D,Q)))
result2 =
2019 May 27
0
opus-1.3.1 patch for ARM Cortex-M4F (single precision)
...f (tonal->highE[b] > tonal->lowE[b] + 7.5f)
{
if (tonal->highE[b] - logE[b] > logE[b] - tonal->lowE[b])
tonal->highE[b] -= .01f;
@@ -700,7 +700,7 @@ static void tonality_analysis(TonalityAn
L2 += tonal->E[i][b];
}
- stationarity = MIN16(0.99f,L1/(float)sqrt(1e-15+NB_FRAMES*L2));
+ stationarity = MIN16(0.99f,L1/(float)sqrt(1e-15f+NB_FRAMES*L2));
stationarity *= stationarity;
stationarity *= stationarity;
frame_stationarity += stationarity;
@@ -748,7 +748,7 @@ static void tonality_analysis(Tonal...
2005 May 02
1
Trying to understand kpss.test() in tseries package
...quot;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 <- rnorm(1000) # is level stationary
> kpss.test(x, null="Level")
KPSS Test for Level Stationarity
KPSS Level = 0.0638, Truncation lag parameter = 7, p-value = 0.1
Warning: p-value greater than printed p-value
> kpss.test(x, null="Trend")
KPSS Test for Trend Stationarity
KPSS Trend = 0.0275, Truncation lag parameter = 7, p-value = 0.1
Warning: p-value greater than printed...
2005 Jan 25
1
CODA vs. BOA discrepancy
...z-score p-value Z-Score p-value
b[1] 1.143 0.253 0.000 1.000
b[2] 0.470 0.638 0.056 0.956
b[3] -1.037 0.300 -0.388 0.698
b[4] -0.618 0.536 -0.085 0.933
tau -0.206 0.837 -0.008 0.994
sigma 0.716 0.474 0.437 0.662
CODA -- Heidelberger and Welch
Stationarity start p-value
test iteration
b[1] passed 1 0.2649
b[2] passed 1 0.6709
b[3] passed 1 0.6376
b[4] passed 1 0.3673
tau passed 1 0.1944
sigma passed 1 0.0725
Halfwidth Mean Halfwidth...
2008 Jan 10
1
question regarding kpss tests from urca, uroot and tseries packages
...276, 313, 292, 302,
322, 281, 298, 305, 295, 286, 327, 286, 270, 289, 293, 287,
267, 267, 288, 304, 273, 264, 254, 263, 265, 278)
x <- ts(x, frequency = 12)
library (urca)
library (uroot)
library (tseries)
Now, doing an ur.kpss test (mu, lag=3) i cannot reject the null hypothesis of level stationarity.
Doing a kpss.test (mu, lag=1 by default ) the p value becomes smaller than 0.05 thus rejecting the null of stationarity. Same with KPSS.test (lag=1)
So, as i have noticed that increasing the number of lags on each of the tests rejecting the null becomes harder and harder. I saw that books always...
2002 Jan 11
2
new dgamma rate argument
Can someone explain to me in what way the new (dpqr)gamma parameter
can be interpreted as a rate (when shape != 1)? The only gamma rate
that I am aware of is the hazard rate given by dgamma/(1-pgamma), the
log of which is returned by my hgamma function (event library).
Jim
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2008 May 20
4
are 588 sample frames subset or nonsubset?
Hi
I am thinking of ripping albums to a single flac file with embedded
cuesheet. As track and index points have to be on a 588 sample boundary due
to the CD TOC standard working in 588 sample frames, I thought it may be
beneficial to rip CDs with a blocksize of 588 samples.
According to the format page on sourcefourge a stream is subset if
"The blocksize bits in the frame header must be
2004 Jul 19
1
(no subject)
hello R experts,
my question is regarding arma modelling and specification.
in another older, statistics package , after determining stationarity, i would try to work out the number of ar and ma lags using an lm test.
to do this i would
1. regress my dependant variable on an intercept term then
2. use LM test for serial correlation, and finally
3. use the p value of the ols residuals to get the maximum lags for the arma specification.
I...