Displaying 20 results from an estimated 10000 matches similar to: "list assignment"
2011 Apr 04
1
simulating a VARXls model using dse
Hello,
Using the dse package I have estimated a VAR model using estVARXls().
I can perform forecasts using forecast() with no problems, but when I
try to use simulate() with the same model, I get the following error:
Error in diag(Cov, p) :
'nrow' or 'ncol' cannot be specified when 'x' is a matrix
Can anyone shed some light on the meaning of this error? How can I
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
2012 Nov 21
0
Question about VAR (Vector Autoregression) in differences.
Folks,
I have been using the VAR {vars} program to find a fit for the following bi-variate time series (subset):
bivariateTS<-structure(c(0.950415958293559, 0.96077848972081, 0.964348957109053,
0.967852884998915, 0.967773510751625, 0.970342843688257, 0.97613937178359,
0.980118627997436, 0.987059493773907, 0.99536830931504, 1.00622672085718,
1.01198013845981, 1.01866618122606,
2005 Oct 30
1
question on adding confidence intervals
I am trying to do a forecasting exercise for a series, x. My forecast
model consists of the following
I first regress log(x) on time and dummy variables for each month.
lm(log(x) ~ time + monthly dummies)
I then use predict() to obtain a prediction for the next year.
I then fit an AR(6)/AR(12) model on the residuals of the regression.
I use predict() here also to obtain the prediction for the
2018 Jun 01
2
Time-series moving average question
My guess would be that if you inspect the output from
ma(dat3[1:28], order=3)
you will find some NAs in it. And then forecast() doesn't like NAs.
But I can't check, because I can't find the ma() and forecast() functions. I assume they come from some package you installed; it would be helpful to say which package.
-Don
--
Don MacQueen
Lawrence Livermore National Laboratory
7000
2007 May 30
2
S4 assignment \alias and \usage
What is the Rd file alias and usage syntax for an S4 assignment method?
I have been trying variations on
\alias{TSdoc<-,default-method}
\usage{
\S4method{TSdoc}{default}(x) <- value
but so far I have not got it right according to various codoc, etc, checks.
Paul Gilbert
====================================================================================
La version fran?aise
2010 Oct 07
1
Forecasting with R/Need Help. Steps shown below with the imaginary data
1. This is an imaginary data on monthly outcomes of 2 years and I want to forecast the outcome for next 12 months of next year.
data Data1;
input Yr Jan Feb Mar Apr May June July Aug Sept Oct Nov Dec;
datalines;
2008 12 13 12 14 13 12 11 15 10 12 12 12
2009 12 13 12 14 13 12 11 15 10 12 12 12
;
run;
I converted the above data into the below format to use it in R as it was giving error: asking
2011 Apr 12
1
How to set the dimension of a matrix correctly?
Hi all,
I use kriging to interpolate the precipitation from stations, but the map of this results show lots of stripes. (please see the attachment)I think there's something wrong with the setting of the dimension of this matrix, however, I have no idea how to know or test to see if this setting is correct or not.I've tried to switch the latitude and longitude, but still got the same
2010 Feb 07
1
Out-of-sample prediction with VAR
Good day,
I'm using a VAR model to forecast sales with some extra variables (google
trends data). I have divided my dataset into a trainingset (weekly sales +
vars in 2006 and 2007) and a holdout set (2008).
It is unclear to me how I should predict the out-of-sample data, because
using the predict() function in the vars package seems to estimate my
google trends vars as well. However, I want
2009 Mar 05
3
Time Series - ARIMA differencing problem
Hi,
I have been using this website (
http://www.stat.pitt.edu/stoffer/tsa2/Rissues.htm
http://www.stat.pitt.edu/stoffer/tsa2/Rissues.htm ) to help me to fit ARIMA
models to my data. At the moment I have two possible methods to use.
Method 1
If I use
arima(ts.data, order=c(1,2,0), xreg=1:length(ts.data))
then the wrong value for the intercept/mean is given (checked on SPSS and
Minitab) and
2008 Oct 22
1
forecasting earnings, sales and gross margin of a company...
Hi all,
I am playing with some companies' balance sheets and income statements
and want to apply what I've just learned from Stats class to see if I
can forecast the companies earnings, sales and gross margin in the
short term (3rd and 4th Quarter), mid-term (2009) and long term (2011,
etc. )
I pulled up some data from companies' financial statements over the
past a few years. The
2009 Nov 19
2
Problem with zoo and BootPR packages
Hi,
I'm trying to plot the forecasts I generated using the Plot.Fore function of the BootPR package.
But I got an error from zoo:
My data:
Time Series:
Start = 1
End = 18
Frequency = 1
[1] 38731 38628 39117 92809 71984 31226 58613 72360 107956 92066
[11] 95208 99098 95848 120383 110717 105680 98469 101916
Script:
y1<-ts(y1);
2012 Nov 07
2
pseudo R-squared with likfit (geoR)
We want to compute a pseudo R-squared for a model whose parameter
estimation was based on maximum likelihood (function likfit, package geoR).
I tried to compute the R2 proposed by Maddala (1983) which compare the
maximized likelihood for the model without any predictor and the
maximized likelihood for the model with all predictors.
I got a really low value (0,01%). Did I miss something? Are
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 =
2010 Jan 11
1
HoltWinters Forecasting
Hi R-users,
I have a question relating to the HoltWinters() function. I am trying to
forecast a series using the Holt Winters methodology but I am getting some
unusual results. I had previously been using R for Windows version 2.7.2 and
have just started using R 2.9.1. While using version 2.7.2 I was getting
reasonable results however upon changing versions I found I started to see
unusual
2011 Nov 11
1
Formula variable help
I have an R script with the following applicable lines:
xshort <- window(s, start=st, end=ed)
. . .
xshort <- ts(xshort, frequency=1, start=1)
. . .
m1 <- m2 <- m3 <- m4 <- m5 <- m6 <- NULL
m1 <- tslm(xshort ~ trend)
I get an error:
Error in get(dataname) : object 'xshort' not found
When I do traceback() I get:
3: get(dataname)
2: tslm(xshort ~
2018 Jun 01
0
Time-series moving average question
Good morning, I hope someone can help with these questions, or perhaps suggest one of the other R-lists?
I have two questions:
1. Why am I getting this warning?
2. Why is the second example "Point Forecast" the same value, I do not see that in previous attempts with similar but different data sets as in example 1?
Example1:
dat3 <- structure(c(3539122.86, 3081383.87,
2010 Jun 28
1
Exponential Smoothing: Forecast package
Hey,
I am using the ets() function in the forecast package to find out the best
fit parameters for my time-series. I have about 50 sets of time series data.
I'm currently using the function as follows:
ets(x,model="AZZ",opt.crit="mse")
As to my observation about 5-10 of them have been identified by ets to have
a trend and an alpha, beta values have been thrown up -
2011 Oct 28
0
problem with glsm.krige: trendd and trend l must have similar specifications error
Hello,
I used glsm.mcmc and likfit.glsm to create model. Now I want to predict at different locations, but I can't get glsm.krige to work. I keep getting the error that trend.d and trend.l must have similar specifications. I have tried numerous ways to include the covariates in the glsm.krige model, and I keep getting the same error message. The bolded part is the part that doesn't work.
2010 Aug 19
1
How to include trend (drift term) in arima.sim
I have been trying to simulate from a time series with trend but I don't see
how to include the trend in the arima.sim() call. The following code
illustrates the problem:
# Begin demonstration program
x <- c(0.168766559, 0.186874000, 0.156710548, 0.151809531, 0.144638812,
0.142106888, 0.140961714, 0.134054659, 0.138722419, 0.134037018,
0.122829846, 0.120188714,