Displaying 20 results from an estimated 700 matches similar to: "AIC and BIC from arima()"
2007 Sep 07
1
negative value for AIC and BIC
Hi all,
I obtained negative values for AIC and BIC criteria for a particular
model that I have
developped...
I don't remember to have negative values for these crietria for others
applications, so I am a
little suprised... Could anyone tell me if something is wrong or his
conclusion concerning my model?
Best regards,
Olivier.
2007 Jan 24
1
n step ahead forecasts
hello,
I have a question about making n step ahead forecasts in cases where test
and validation sets are availiable. For instance, I would like to make one
step ahead forecasts on the WWWusage data so I hold out the last 10
observations as the validation set and fit an ARIMA model on the first 90
observations. I then use a for loop to sequentially add 9 of the holdout
observations to make 1
2007 Dec 27
1
AIC and BIC in mixed effects model
Dear R Users:
I am trying to compare several structures of the within-patient covariance
such as unstructured, Autoregressive, and spatial by using the MIXED effects
model. Can AIC, BIC be negative ? If yes, then in what situations they may
be negative.
Thanks a lot.
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2023 Aug 12
1
time series transformation....
dear members,
I have a heteroscedastic time series which I want to transform to make it homoscedastic by a box cox transformation. I am using Otexts by RJ hyndman and George Athanopolous as my textbook. They discuss transformation and also say the fpp3 and the fable package automatically back transforms the point forecast. they also discuss the process which I find to be
2006 Jun 10
2
R usage for log analysis
Hello,
Is there any software project that uses R to do log file analisys?
thanks
gabi
2018 Mar 02
0
Rstmp2 - linear predictors, AICs and BICs
Dear R-help,
I am using R-3.3.2 on Windows 10. As per my previous post today, I teach on a course which has 4 computer practical sessions related to the development and validation of clinical prediction models. These are currently written for Stata and I am in the process of writing them for use in R too (as I far prefer R to Stata!)
Part of the practical requires the student to fit a flexible
2003 Sep 29
1
BIC or AIC from nnet
Is AIC or BIC available when using the
nnet package?
Thank you
Paul Green
2006 Apr 20
1
Extract AIC, BIC
Hi All,
How can extract AIC,BIC from a fitted Garch model?
--
SUMANTA BASAK.
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2004 Apr 26
1
AIC and BIC
Hello
I'm with a doubt using BIC and AIC. I want to know if both of then are a way
to steem the best model to use. How i know which of then to choose?
Talita Perciano Costa Leite
Graduanda em Ci??ncia da Computa????o
Universidade Federal de Alagoas - UFAL
Departamento de Tecnologia da Informa????o - TCI
Constru????o de Conhecimento por Agrupamento de Dados - CoCADa
2008 May 23
0
Est. Component Size with AIC/BIC under Gamma Distribution
Dear all,
I am trying to model number of samples from
a given series. The series are modelled according
Gamma function.
In order to estimate the # samples, I use BIC/AIC
with MLE (computed from dgamma function).
Here is the code I have.
__BEGIN__
mlogl <- function( x_func, theta_func, samp) {
# computing log_likelihood
return( - sum(dgamma(samp, shape = x_func, scale=theta_func, log
2009 Aug 20
1
definition of AIC and BIC in gls
Hello everybody,
Please help with connecting the AIC and BIC numbers printed by summary.gls to the logLik number.
1. is the logLik number the true ML or density scaling constants have been omitted?
2. what is the formula for calculating the AIC and BIC from logLik (and how can I see it)? I tried printing summary.gls but it says object not found.
Thank you very much.
Stephen
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2012 May 18
0
Forecast package, auto.arima() convergence problem, and AIC/BIC extraction
Hi all,
First:
I have a small line of code I'm applying to a variable which will be
placed in a matrix table for latex output of accuracy measures:
acc.aarima <- signif(accuracy(forecast(auto.arima(tix_ts,
stepwise=FALSE), h=365)), digits=3).
The time series referred to is univariate (daily counts from 12-10-2010
until 5-8-2010 (so not 2 full periods of data)), and I'm working on
2007 Jan 12
1
R2WinBugs and Compare DIC versus BIC or AIC
Dear All
1)
I'm fitting spatial CAR models
using R2Winbugs and although everything seems to go reasonably well (or I
think so)
the next message appears from WINBUGS 1.4 window:
gen.inits()
Command #Bugs: gen.inits cannot be executed (is greyed out)
The question is if this message means that something is wrong and the
results are consequently wrong, or Can I assume it as a simple warning
2011 Oct 19
1
ar() - AIC and BIC
Hi,
I'm slowly working through Tsay's "Analysis of Financial Time Series"
3rd ed. ?I'm trying to replicate Table 2.1 on p.47, which gives PACF,
AIC, and BIC for the monthly simple returns of the CRSP value-weighted
index.
The data:
http://faculty.chicagobooth.edu/ruey.tsay/teaching/fts3/m-ibm3dx2608.txt
> da <-
2006 Oct 18
1
lmer- why do AIC, BIC, loglik change?
Hi all,
I am having issues comparing models with lmer. As an example, when
I run the code below the model summaries (AIC, BIC, loglik) differ between
the summary() and anova() commands. Can anyone clear up what's wrong?
Thank you!
Darren Ward
library(lme4)
data(sleepstudy)
fm1<-lmer(Reaction ~ Days + (1|Subject), sleepstudy)
summary(fm1)
fm2<-lmer(Reaction ~ Days +
2006 Jun 05
2
Calculation of AIC BIC from mle
R 2.3.0, all packages up to date
Linux, SuSE 10.0
Hi
I want to calculate AIC or BIC from several results from mle calculation.
I found the AIC function, but it does not seem to work with objects of
class mle -
If I execute the following:
ml1 <- mle(...)
AIC(ml1)
I get the following error messale:
Error in logLik(object) : no applicable method for "logLik"
Therefore I am using the
2010 Jul 05
2
Can anybody help me understand AIC and BIC and devise a new metric?
Hi all,
Could anybody please help me understand AIC and BIC and especially why do
they make sense?
Furthermore, I am trying to devise a new metric related to the model
selection in the financial asset management industry.
As you know the industry uses Sharpe Ratio as the main performance
benchmark, which is the annualized mean of returns divided by the annualized
standard deviation of returns.
2009 Mar 18
3
Extreme AIC or BIC values in glm(), logistic regression
Dear R-users,
I use glm() to do logistic regression and use stepAIC() to do stepwise model
selection.
The common AIC value comes out is about 100, a good fit is as low as around
70. But for some model, the AIC went to extreme values like 1000. When I
check the P-values, All the independent variables (about 30 of them)
included in the equation are very significant, which is impossible, because
we
2005 Sep 08
2
Time Series Analysis: book?
There has been a few questions on the subject lately.
Is there any book on the subject, if possible with a computer processing flavor,
that you would highly recommend?
Many thanks in advance,
--
Jean-Luc
2016 Apr 07
4
Contenido de un objeto/modelo ARIMA
Buenos días,
Os cuento:
Cargo la librería "Forecast" y ejecuto su función Arima(...) sobre una
serie temporal:
mimodelo <- Arima(miST$miserie, ...);
Ahora si ejecuto las siguientes sentencias, voy obteniendo los resultados
contenidos en "mimodelo", pero algunos de ellos no sé lo que son:
mimodelo[[1]] obtengo los coeficientes del modelo ARIMA
mimodelo[[2]] obtengo el