Displaying 20 results from an estimated 43 matches for "burnham".
2007 Mar 09
4
Reg. strings and numeric data in matrix.
...'s with characters (strings) data? How do I get this type of
data from a flat file.
Thanks very much,
mallika
____________________________________________________________________________
Mallika Veeramalai, Ph.D.,
Postdoctoral Associate,
Bioinformatics & Systems Biology,
Burnham Institute for Medical Research,
La Jolla, CA 92037, USA.
phone : +1 858 646 3100 ext: 3627
Fax : +1 858 795 5249
Web : http://bioinformatics.burnham.org/~mallika/
Email : mallikav at burnham.org (or) kaaviyam at gmail.com
2008 Apr 20
1
Reg. consensus ranking
...vailable in R for this purpose? I will appreciate any pointers in this regard.
Thank you very much in Advance,
Mallika
*~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~*
Mallika Veeramalai, PhD,
Postdoctoral Associate,
Bioinformatics & Systems Biology,
Prof. Adam Godzik Lab,
Burnham Institute for Medical Research,
La Jolla, San Diego, CA 92037, US.
phone : +1 858 646 3100 ext: 3627 (work)
Fax : +1 858 795 5249
Web : http://bioinformatics.burnham.org/~mallika/
Email : mallikav at burnham.org
kaaviyam at gmail.com
*~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~...
2011 Mar 24
3
How create vector that sums correct responses for multiple subjects?
...ng:
nrow(pretestdata[(pretestdata$Subject=="1" & pretestdata$Correct=="C"),])
gives the number of correct responses for subject 1, but I would like a
vector that indicates the number correct for each of 33 subjects.
Thank you sincerely for your assistance.
Kevin Burnham
[[alternative HTML version deleted]]
2003 Jul 04
1
Quasi AIC
Dear all,
Using the quasibinomial and quasipoisson families results in no AIC being
calculated. However, a quasi AIC has actually been defined by Lebreton et al
(1992). In the (in my opinon, at least) very interesting book by Burnham and
Anderson (1998,2002) this QAIC (and also QAICc) is covered. Maybe this is something
that could be implemented in R.
Take a look at page 23 in this pdf:
http://www.springer-ny.com/supplements/0387953647/Preface_Contents_and_Chapter_8.pdf
Lebreton, J-D et al. (1992) Modeling Survival and Testi...
2004 Jun 01
1
multi-model inference
Hello
I've been investigating using multi-model inference, based on calculating
AIC and AIC weights, using the techniques outlined in Burnham and
Anderson's (2002) book. However I notice a couple of emails in the R-help
archive stating that there are errors in the technique. Are these errors
associated with the particular implementation that B & A propose in their
text, or is the whole approach flawed in some way?
Many thanks...
2006 Feb 20
1
Nested AIC
Greetings,
I have recently come into some confusion over weather or not AIC
results for comparing among models requires that they be nested.
Reading Burnham & Anderson (2002) they are explicit that nested
models are not required, but other respected statisticians have
suggested that nesting is a pre-requisite for comparison. Could
anyone who feels strongly regarding either position post their
arguments for or against nested models and AIC?...
2010 May 31
2
Ignoring initial rows in a text file import
...\tPressed\t(any response)\tC\t25860\t\t\t\t\t"
I would also like it to ignore the row:
[173] "Main Group\t1000\tBreak\tBreak\
tpause3\t\t \tPressed\t(any response)\tC\t47610\t\t\t\t\t"
which will always be the same number of rows after the "Begin Main" row.
Thanks,
Kevin Burnham
[[alternative HTML version deleted]]
2003 Mar 04
1
Sample size and stepAIC, step, or AIC
Do any R functions incorporate a sample sample size correction (e.g.,
Burnham and Anderson 1998).
Thanks,
Hank Stevens
Martin Henry H. Stevens, Assistant Professor
338 Pearson Hall
Botany Department
Miami University
Oxford, OH 45056
Office: (513) 529-4206
Lab: (513) 529-4262
FAX: (513) 529-4243
http://www.cas.muohio.edu/botany/bot/henry.html
http://www.muohio.edu/ecology
2011 Jun 03
1
Outputting data from TukeyHSD
...have used capture.output(tukey.contrast, file="tukey.contrast.xls")
and this works, but the data are not in a table form, and so it is sort of a
pain to manipulate the output.
I have be unable to find a more convenient way and any assistance would be
greatly appreciated.
Thanks,
Kevin Burnham
[[alternative HTML version deleted]]
2006 Jan 30
4
Logistic regression model selection with overdispersed/autocorrelated data
...n. Robust standard errors are
easily calculated by block-bootstrapping the data using animal as a
cluster with the Design library, however I havent found a satisfactory
solution for model selection.
A couple options are:
1. Using QAIC where the deviance is divided by a variance inflation factor
(Burnham & Anderson). However, this VIF can vary greatly depending on the
data set and the set of covariates used in the global model.
2. Manual forward stepwise regression using both changes in deviance and
robust p-values for the beta-coefficients.
I have been looking for a solution to this problem...
2005 Oct 29
2
LaTex error when creating DVI version when compiling package
...e between AIC and the
lowest AIC value; w_i, the Akaike weights; AICc, the second order Akaike
criterion; deltAICc, the difference between AICc and the lowest AICc
value; w_ic, the AICc weights }
\item{models}{the list of models}
}
\references{
Anderson, D.R., Link, W.A., Johnson, D.H. and Burnham, K.P. (2001).
Suggestions for presenting the results of data analyses. Journal of
Wildlife Management, 65, 373-378; Burnham, K.P. and Anderson, D.R.
(2002) Model Selection and Multimodel Inference: a Practical
Information-Theoretic Approach, 2nd edn., Springer-Verlag, New York. 353 pp
}
\autho...
2003 Sep 04
1
AIC and significance tests
Hi
I have two geostatistical models from geoR. An ordinary kriging model with
AIC=-148.6 and a universal kriging model with AIC=-156.7, there are 345
data points. The improvement shown by the AIC by adding a trend component
to the model seems quite small given the number of data points, is there a
test to see if the improvement to the model fit is significant?
Thanks
David
2005 Jul 03
1
code for model-averaging by Akaike weights
...rameters by Akaike weights,
and/or to do all-possible-subsets lm modelling that reports parameter
estimates, AICc and number of parameters for each model?
I have been looking for these in the archive but found none.
(I am aware that many of you would warn me against these methods
advocated by Burnham and Anderson 2002, please do not.)
Thank you,
VB
-------------------------------------------------------------------------------
[freemail] extra 1GB-os postafi??kkal, ??nnek m??r van? http://freemail.hu
2008 Jan 24
0
possible inconsistency in nlme logLik or me
...something wrong?????
Information for model 1
rss=sum(resid(mod1)^2)=1318.645
var=rss/n=1.654511
n=797
number of parameters (K) = 10 (this does include the variance estimate)
if I use logLik(mod1) I get -1331.541 with 10 d.f.
if I use the formula:
(-.5*n*log(var))-(797/2*log(2*pi))-(n/2)
from Burnham and Anderson 2002 page 12,
I get the same result as above: -1331.541
Information for model 2 with a correlation structure corr=corExp(form=~lat+lon,nugget=T)
rss=1338.92
n=797
var=rss/n=1.679950
K=12
logLik(mod2)=-1313.65 with 12 d.f.
If I use the equation from Burnham and Anderson I get:...
2008 Jun 21
1
stepAIC {MASS}
In a generalized linear model with k covariates, there are 2(kth power) - 1
possible models (excluding interactions).
Awhile ago a posting to R-help suggested Model Selection and Multimodel
Inference, 2nd ed, by Burnham and Anderson as a good source for
understanding model selection. They recommend (page 71) computing AIC
differences over all candidate models in the set of possible models.
After looking at the help page for stepAIC and checking MASS, I am not
certain which AICs are estimated by stepAIC.
Comments...
2010 Sep 15
2
labeling outliers with subject numberss
How can I get the outlier in this boxplot of "Score" to be represented by
the corresponding value in "SubNo"?
score=c(6,6,7,14,5,7,6,8)
SubNo=1:8
mydata=data.frame(SubNo, score)
boxplot(mydata$score)
Thanks!
Kevin
[[alternative HTML version deleted]]
2011 Apr 30
3
using tapply with multiple variables
HI All,
I have a long data file generated from a minimal pair test that I gave to
learners of Arabic before and after a phonetic training regime. For each of
thirty some subjects there are 800 rows of data, from each of 400 items at
pre and posttest. For each item the subject got correct, there is a 'C' in
the column 'Correct'. The line:
tapply(ALLDATA$Correct,
2008 May 07
2
Estimating QAIC using glm with the quasibinomial family
...a simple
solution:
"we calculated QAICc adjusting for overdispersion by dividing the
residual deviance (i.e. -2 loglikelihood) with the overdispersion
parameter calculated from the most complex model as the sum of squares
Pearson residuals divided by the number of degrees of freedom (Burnham
& Anderson, 2002). "
- Mystrud et al. 2007. Animal Conservation. 10:77-87.
My question is: Will this calculation be valid with the residual
deviance returned by the glm() function using the quasibinomial family
as reported in R?
I thought I should ask to be certain that there is...
2008 Feb 04
1
extracting AIC scores from lmer and other objects
I have a slight conundrum. I'm attempting to write a scrip that will
take a number of objects (lm, glm, and lmer) and return AIC scores
and weights. I've run into 3 problems, and was wondering if anyone
had any pointers.
1) is there any convenient way to extract the name of the objects?
Simply, if I have a vector of objects c(my.lm, my.lmer) and I want to
get a character