Displaying 20 results from an estimated 9000 matches similar to: "[Q] BIC as a goodness-of-fit stat"
2010 Jan 06
1
positive log likelihood and BIC values from mCLUST analysis
My question is with respect to mCLUST and the values of BIC and log
likelihood. The relevant part of my R script is:
######################### BEGIN MDS ANALYSIS #########################
#load data
data <- read.table("Ecoli33_Barry.dis", header = TRUE, row.names = 1)
#perform MDS Scaling
mds <- metaMDS(data, k = Dimensions, trymax = 20, autotransform =TRUE,
noshare = 0.1,
2003 Apr 24
1
AW: estimating number of clusters ("Null or more")
Dear Christian,
first of all thank you for your answer. I am going to parse through
the pages you told me. Meanwhile I'd like to note that probably it
is a good idea to put 2-3 lines of R-code demonstrating such a
simple needs somnewhere in docs of `cluster' package. E.g.
x<-rnorm(500)
... # output means we have rather 1 claster
x<-c(rnorm(500), rnorm(500)+5)
2003 Aug 05
2
Error on mclust
Hi All,
I am trying to cluster a one-dimensional data (see the file attached) using
Mclust() but got an error message like:
>Mclust(x)
Error in rep(1, n) : Object "n" not found
When I do a simulation sometimes it works sometimes doesn't.
>Mclust(c(rnorm(50),rnorm(56,-0.5)))
Error in rep(1, n) : Object "n" not found
>Mclust(c(rnorm(56),rnorm(56,-0.5)))
best
2002 Feb 14
1
Subsets in mclust
Dear group,
I want to use the mclust package on large data, and therefore I want to use
a subset in the initial clustering phase. From help(mclust):
k: If `k' is specified, the hierarchical clustering phase will
use a sample of size `k' of the data in the initial
hierarchical clustering phase. The default is to use the
entire data set.
m2 is a
2006 Oct 19
1
[Q] How to fit data to a straight line
Dear R users
I have a question about how to fit data to a straight line.
I tried nls to do it, but it didn't work.
The reason I want to fit data to a straight line is that I need to compare
AIC or BIC values of the two models (a straight line model vs a nonlinear
curve model). Fitting data to a nonlinear curve is straightforward, but I
could not figure out how to fit the data to a straight
2006 Jan 05
4
Q: R 2.2.1: Memory Management Issues?
Dear Developers:
I have a question about memory management in R 2.2.1 and am wondering if you would be kind enough to help me understand what is going on.
(It has been a few years since I have done software development on Windows, so I apologize in advance if these are easy questions.)
-------------
MY SYSTEM
-------------
I am currently using R (version 2.2.1) on a PC running Windows 2000
2009 Apr 05
1
Which model to keep (negative BIC)
Hi,
My questions concern the function 'mclustBIC' which compute BIC for a range of clusters of several models on the given data and the other function 'mclustModel' which choose the best model and the best number of cluster accordind to the results of the previous cited function.
1) When trying the following example (see ?mclustModel), I get negative BIC computed by
2003 Sep 11
3
Rgui access violation
Dear All;
While using EMclust() in the mclust package, I frequently
encountered a program error. A message window popped up with the message "
Rgui.exe has generated errors and will be closed by Windows. You will need
to restart the program. An error log is be created."
> version
_
platform i386-pc-mingw32
arch i386
os mingw32
2005 Oct 21
1
finite mixture model (2-component gaussian): plotting component gaussian components?
Dear Knowledgeable R Community Members,
Please excuse my ignorance, I apologize in advance if this is an easy question, but I am a bit stumped and could use a little guidance.
I have a finite mixture modeling problem -- for example, a 2-component gaussian mixture -- where the components have a large overlap, and
I am trying to use the "mclust" package to solve this problem.
I need
2004 Oct 04
3
Help with normal distributions
Hi
I have two questions, the first perhaps dumber than the second.
Firstly, I have a data set, and when I plot a histogram it looks like a
normal distribution. So I want to overlay a bell-shaped normal
distribution on top of it, to demonstrate how similar it is to the
normal distribution. I have read the help on dnorm(), rnorm(), pnorm()
etc but still can't figure out how to plot a normal
2003 Nov 16
1
help with EMclust
we have implemented teh following code for determinging the clustering
model of a dataset.
bicvals <- EMclust( hdata, 7)
sumry1 <- summary(bicvals, hdata,7) # summary object for emclust()
print(sumry1)
This set of code gives the following output
classification table:
1 2 3 4 5 6 7
1 1 1 4 1 1 1
which I think means there is 1 gene in the 1st cluster...1 gene in the
2nd cluster ,
2003 Apr 24
1
estimating number of clusters ("Null or more")
Hi all,
once more about the old subj :-)
My data has too much various distribution families and for every
particular experiment
I need just to decide whether the data is "quite homogeneous" or it has
two or more
clusters. I've revisited the following libraries:
amap, clust, cclust, mclust, multiv, normix, survey.
And I didn't find any ready-to-use general
2003 Jul 17
3
univariate normal mixtures
Hello,
I have a concrete statistical question:
I have a sample of an univariate mixture of an unknown number (k) of
normal distributions, each time with an unknown mean `m_i' and a
standard deviation `k * m_i', where k is known factor constant for all
the normal distributions. (The `i' is a subscript.)
Is there a function in R that can estimate the number of normal
distributions k
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
2003 Apr 23
1
clustering
Dear R-users,
I have a two - dimensional data set which needs to be clustered into
groups:
I'm searching for groups of points which show a positive
correlation (in a twodimensional plot of the data set), but I do not have
any knowledge about how many groups there might be.
Do you know of a clustering algorithm in R (or
in general) which can use a-priori information about the cluster's
2003 May 07
1
-means, hybrid clustering or similar implementations on R
Hi,
I would like to know if someone knows an extended implementation of k-means in R to find appropriate number of clusters for a given k-dimensional data.
Also, I am working on clustering for forecasting, if someone is interested or has knowledge on implementational details please mail me, I would appreciate it.
Regards
Skanda Kallur
"Cogito, ergo sum" (I think, therefore I
2002 Dec 13
1
clustering dissimilarities
Hello. I know my dissimilarity matrix but not my original data. Is there any way i could use the clustering function Mclust or EMclust with this dissimilarity matrix? or at least some equivalent of these functions? As this is model based clustering i dont know if it is actually possible to do it without the original data
thanks in advance for your help
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2004 Jun 07
2
MCLUST Covariance Parameterization.
Hello all (especially MCLUS users).
I'm trying to make use of the MCLUST package by C. Fraley and A. Raftery. My problem is trying to figure out how the (model) identifier (e.g, EII, VII, VVI, etc.) relates to the covariance matrix. The parameterization of the covariance matrix makes use of the method of decomposition in Banfield and Rraftery (1993) and Fraley and Raftery (2002) where
2005 Nov 28
1
AIC and BIC from arima()
-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1
My ultimate goal is to best fit time series by comparing AICs and BICs
(as in Bayesian) from arima() and nnet().
I looked at the arima.R source code, but I am afraid I do not
understand it.
What I only miss really is the number of parameters p, where: AIC =
n*log(S/n) + 2*p
with S the squared residuals and n the number of observations.
Can I get p
2005 Apr 18
2
Why no BIC.default function?
I'm using R 2.0.1.
I looked in the email archives but didn't see anything on this topic.
I've noticed a surprising (to me) difference between AIC and BIC:
> methods("AIC")
[1] AIC.default* AIC.logLik*
> methods("BIC")
[1] BIC.gls* BIC.lm* BIC.lme* BIC.lmList* BIC.logLik* BIC.nls*
The BIC.gls BIC.lm BIC.lme BIC.lmList and BIC.nls functions appear