Displaying 20 results from an estimated 400 matches similar to: "how to reduce stress value in isoMDS?"
2005 Jun 14
1
using forecast() in dse2 with an ARMA model having a trend component
(My apologies if this is a repeated posting. I couldn't find any trace
of my previous attempt in the archive.)
I'm having trouble with forecast() in the dse2 package. It works fine
for me on a model without a trend, but gives me NaN output for the
forecast values when using a model with a trend. An example:
# Set inputs and outputs for the ARMA model fit and test periods
2006 Jan 03
2
KALMAN FILTER HELP
Hi All,
Currently I'm using DSE package for Kalman Filtering. I have a dataset
of one dependent variable and seven other independent variables. I'm
confused at one point. How to declare the input-output series using
TSdata command. Because the given example at page 37 showing some error.
rain <- matrix(rnorm(86*17), 86,17)
radar <- matrix(rnorm(86*5), 86,5)
mydata <-
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
2006 Jun 26
2
converting to time series object : ts - package:stats
Hi,
I am trying to convert a dataset (dataframe) into time series object using ts function in stats package. My dataset is as follows:
>df
[1] 11.08 7.08 7.08 6.08 6.08 6.08 23.08 32.08 8.08 11.08 6.08 13.08 13.83 16.83 19.83 8.83 20.83 17.83
[19] 9.83 20.83 10.83 12.83 15.83 11.83
I converted this into time series object as follows
>tsdata <-
2003 Apr 14
1
isoMDS and stress
Hi all,
I try to calculate the stress of a configuration using the formula in
the isoMDS help, but I don't have the same result than the stress
returned by isoMDS :
> library(mva)
> library(MASS)
> data(swiss)
> swiss.x <- as.matrix(swiss[,-1])
> swiss.dist <- dist(swiss.x)
> swiss.mds <- isoMDS(swiss.dist)
initial value 2.979731
iter 5 value 2.431486
iter 10
2017 Sep 15
0
require help
> On 15 Sep 2017, at 11:38, yadav neog <yadavneog at gmail.com> wrote:
>
> hello to all. I am working on macroeconomic data series of India, which in
> a yearly basis. I am unable to convert my data frame into time series.
> kindly help me.
> also using zoo and xts packages. but they take only monthly observations.
>
> 'data.frame': 30 obs. of 4 variables:
2011 Nov 22
1
Varma models in the dse package
Hi,
I tried to run the VARMA model in the dse package. I specified a model:
> arma
A(L) =
1+0.244L1 0+0.05L1
0-0.325L1 1-0.234L1
B(L) =
1-0.277L1 0+0.211L1
0-0.206L1 1+0.238L1
and have a TSdata object:
> dfdata
output data:
Series 1 Series 2
1 "difex2" "difem2"
but I get this warning message:
> estMaxLik(arma, dfdata)
Error in
2005 Dec 23
1
dse package problems
I am having problems with the package dse. I just installed R 2.2.1
and reinstalled all packages. I am running Windows XP Pro with all
updates.
Below there are two examples of error messages generated when trying
to execute some simple programs. The code was taken directly from the
package documentation.
Any help on this will be greatly appreciated.
Merry Christmas
Fernando
2014 Jan 08
0
Strange behaviour of `dlm` package
Dear R-help!
I have encountered strange behaviour (that is, far-off filtering, smoothing
and forecast distributions under certain conditions) in the `dlm` package by
Giovanni Petris.
Here is an example:
I use the annual hotel bookings time series data, which I model using a
second order polinomial DLM.
First I perform the analysis with the data in logarithmic form and
everything seems to be
2001 Oct 12
1
MASS: isoMDS and sammon
If tbl is an object of class 'dist', you can do this:
a <- sammon(tbl, k=3)
But you can't do this:
b <- isoMDS(tbl, k=3)
Wouldn't it be sensible to have identical interfaces to sammon()
and isoMDS() ?
I think all that would be needed is to change this:
isoMDS <- function(d, y=cmdscale(d, 2), maxit=50, trace=TRUE)
{
...into this:
isoMDS <-
2009 Aug 30
1
about isoMDS method
Hi,
For example:
I built a half matrix "w" using a daisy(x, metric = c("euclidean"))
http://www.nabble.com/file/p25211016/1.jpg
And next I transformed this matrix "w" using isoMDS function, for example
isoMDS(w, k=2) and as result I got:
http://www.nabble.com/file/p25211016/2.jpg
And now I have two questions:
1. If number in matrix w[2, 1] (= 0.41538462) match
2004 Apr 12
1
question on isoMDS
Hello everyone,
I have a question on isoMDS.
My data set (of vegetation) with 210 samples is in this way:
Rotfoehrenau Lavendelweidenau Silberweidenau ....
067_Breg.7 0 2 0 ....
071_Dona.4 0 2 6 ....
...
I want to do an isoMDS-analysis with the dissimilarity index
2016 Apr 25
1
how to create initial configuraton for isoMDS
Hi,
I'm trying to use isoMDS to project a directed graph to 2-dim vectors, but I got an error.
#here is the code to create the graph using igraph package and run isoMDS on it.
library(igraph)
library(MASS)
g<-make_graph(c(1,2, 2,3, 2,4, 3,4, 4,5, 5,6, 3,6, 1,6, 2,5),directed=TRUE)
dist<-distances(g, mode="out")
loc<-isoMDS(dist)
# below is content of the dist matrix
2008 Sep 01
1
why isoMDS not found?
When I type "isoMDS()" in the R environment, a error shows up: no such
function "isoMDS". Why? And what should I do to use isoMDS? Additionally, I
cannot install add-on packages. Typing "Rcmd.exe INSTALL e:/VR_7.2-44.zip"
results in "'perl' is neither command nor executable file...". Why this
happens?Thanks.
The setup file I downloaded is
2008 Sep 04
2
isoMDS and dist
I am starting with a matrix in which rows are vegetation plots and
columns are various characteristics including ID# and elevation. I
removed elevation and ID columns to avoid having those characteristics
influence the distances between points which I calculated using the
"dist" command. The resulting distance file was then used in isoMDS.
What I want to know is whether I can
2001 Dec 18
2
isoMDS: core dump (PR#1221)
I'm not sure this belong here...
Package: MASS
Version: 6.2-8
I get a core dump when I call isoMDS with an incorrect argument
for y. With d as an object of class "dist":
> isoMDS(d,2)
Program received signal SIGSEGV, Segmentation fault.
0x40229e43 in VR_mds_init_data () at MASS.c:157
--please do not edit the information below--
Version:
platform = i586-pc-linux-gnu
2003 Mar 25
0
isoMDS results
Hi,
this is a second try to post this to the R-help mailing list. The first one
has been rejected because of a too large attachment.
Now I ask this without attaching the data. If you want to reproduce the
results, please contact me directly to get the data.
(First mail, rejected:)
> Attached there is a 149*149 dissimilarity matrix; it is a file obtained by
>
2000 Feb 29
0
Reading the documentation (was isoMDS error message!!!)
> Date: Tue, 29 Feb 2000 17:03:51 +0100 (MET)
> From: Andrea Rossetti <rossetti at markov.stat.unipg.it>
[Mail to your address is undeliverable!!!]
> I do this
>
> > valumod<-read.table("valu-medie.txt",header=T)
> > library(mass)
> > library(mva)
> > valumod.x <- as.matrix(valumod)
> > valumod.dist<-dist(valumod.x)
> >
2006 Oct 21
1
Problems running IsoMDS using vegdist with pres-abs data and two sites with zero distance
Hi
I have just (finally) started to poke around in R and wanted to analyse
a stream fish dataset with 28 sites and 18 species. When trying to
follow the Vegan manual to run nmds from distance measures calculated by
the vegdist function it turns out that I have two sites (streams) with
the exactly the same four species (I have used pres-abs data in this
case). When I try to run isoMDS I get an
2000 Feb 29
0
isoMDS error message!!!
Hi to all,
I do this
> valumod<-read.table("valu-medie.txt",header=T)
> library(mass)
> library(mva)
> valumod.x <- as.matrix(valumod)
> valumod.dist<-dist(valumod.x)
> valumod.mds <- isoMDS(valumod.dist)
Error in isoMDS(valumod.dist) : zero or negative distance between objects 2 and 4
>
Where is the error?
Andrea Rossetti.
PS I've attached the