Displaying 20 results from an estimated 7000 matches similar to: "Data handling/optimum glm method."
2012 Mar 29
2
How to improve, at all, a simple GLM code
Hi There,
I am trying to fit a logit model to some data in a CSV file in R.
Here is my code:
Prepared_Data = read.csv("Prepared_Data.csv", header=TRUE)
Prepared_Data
attach(Prepared_Data)
lrfit<-glm(C3~A1*B2*D4*E5,family = binomial)
anova(lrfit, test="Chisq")
write.csv(anova(lrfit, test="Chisq"), file="CWModelA.csv")
shell.exec("CWModelA.csv")
2002 Oct 31
3
Loess with glm ?
Hello,
I am wondering if there is an easy way to combine loess() with glm()
to produce a locally fitted generalised regression.
I have a data set of about 5,000 observations and 5 explanatory variables,
with a binary outcome. One of the explanatory variables (lets call it X)
is much more predictive than the others. A single glm() regression over
the entire data set produces rather poor results,
2009 Oct 15
2
plotting/examining residuals of a mixed generalised linear model
Dear R users,
I'm hoping that more experienced users will be able to assist me in
examining the model fit of a mixed generalised linear model. The example
using the data 'bacteria' within the MASS package will hopefully illustrate
what I would like to acheive;
library(MASS)
library(nlme)
attach(bacteria) # y being output and the trt - treatment group being an
explanatory variable.
2004 Mar 16
2
glm questions --- saturated model
> -----Original Message-----
> From: r-help-bounces at stat.math.ethz.ch
> [mailto:r-help-bounces at stat.math.ethz.ch] On Behalf Of David Firth
> Sent: Tuesday, March 16, 2004 1:12 PM
> To: Paul Johnson
> Cc: r-help at r-project.org
> Subject: Re: [R] glm questions
>
>
> Dear Paul
>
> Here are some attempts at your questions. I hope it's of some help.
2005 Oct 21
1
Generalised rbind/cbind
Dear list,
Is there a generalised form of rbind/cbind for combining
matrices/arrays into higher-D structures? ie. if I have:
a <- matrix(2,2,2)
b <- matrix(3,2,2)
how can I get
array(rep(c(3,2), each=4), c(2,2,2))
?
It seems like this would be the job of a generalised abind function:
abind(a,b, along=1) == rbind(a,b)
abind(a,b, along=2) == cbind(a,b)
abind(a,b, along=3)
2011 Feb 16
1
Saturated model in binomial glm
Hi all,
Could somebody be so kind to explain to me what is the saturated model
on which deviance and degrees of freedom are calculated when fitting a
binomial glm?
Everything makes sense if I fit the model using as response a vector of
proportions or a two-column matrix. But when the response is a factor
and counts are specified via the "weights" argument, I am kind of lost
as far as
2011 Apr 11
3
multiple comparisons with generalised least squares
Dear R users,
I have used the following model:
M1 <- gls(Nblad ~ Concentration+Season + Concentration:Season, data=DDD,
weights=varIdent(form=~ 1 | Season*Concentration))
to assess the effect of Concentration and Season on nitrogen uptake by
leaves (Nblad). I accounted for the difference in variance across the factor
levels by using the varIdent function.
Then I wanted to perform multiple
2004 Mar 16
2
glm questions
Greetings, everybody. Can I ask some glm questions?
1. How do you find out -2*lnL(saturated model)?
In the output from glm, I find:
Null deviance: which I think is -2[lnL(null) - lnL(saturated)]
Residual deviance: -2[lnL(fitted) - lnL(saturated)]
The Null model is the one that includes the constant only (plus offset
if specified). Right?
I can use the Null and Residual deviance to
2000 Nov 03
3
QUERY: gam models in R?
Hi Allstaters,
Does anybody know if the R package can fit
Generalised Additive Models?.
Thanks indeed,
Aurelio.
atobias at ole.com
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r-help mailing list -- Read
2010 Dec 14
2
Use generalised additive model to plot curve
Readers,
I have been reading 'the r book' by Crawley and think that the
generalised additive model is appropriate for this problem. The
package 'gam' was installed using the command (as root)
install.package("gam")
...
library(gam)
> library(gam)
Loading required package: splines
Loading required package: akima
> library(mgcv)
This is mgcv 1.3-25
Attaching
2001 Jun 11
2
Generalized Additive Model
Hello,
I am wondering if someone can direct me to the syntax of the Generalised
Additive Model in R? In Splus this is gam(formula, ... inputs would be
pretty much the same as glm I suspect..)
Any response on that (or what package should I grap) would be appreciated
very much.
Thanks,
Peppy Adi-Purnomo
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r-help
2003 Feb 19
2
GLM for Beta distribution
Hi R-help,
Is there such a thing as a function in R for fitting a GLM where the
response is distributed as a Beta distribution?
In my case, the response variable is a percentage ([0,1] and continuous).
The current glm() function in R doesn't include the Beta distribution.
Thank you for any help on this topic.
Sincerely,
Sharon K?hlmann
2008 Feb 12
1
Finding LD50 from an interaction Generalised Linear model
Hi,
I have recently been attempting to find the LD50 from two predicted fits
(For male and females) in a Generalised linear model which models the effect
of both sex + logdose (and sex*logdose interaction) on proportion survival
(formula = y ~ ldose * sex, family = "binomial", data = dat (y is the
survival data)). I can obtain the LD50 for females using the dose.p()
command in the MASS
2010 Jun 22
1
Generalised Estimating Equations on approx normal outcome with limited range
Dear R users
I am analysing data from a group of twins and their siblings. The measures
that we are interested in are all correlated within families, with the
correlations being stronger between twins than between non-twin siblings.
The measures are all calculated from survey answers and by definition have
limited ranges (e.g. -5 to +5), though within the range they are
approximately normally
2009 Apr 01
1
Request: Optimum value of cost complexity parameter "k" in "tree" package
Dear R community
I have a question regarding the value of cost complexity parameter "k" used in "tree" package for pruning purpose. Any help in finding the optimum value of "k" is requested. Please give some suggestion in this regard. In the example below i used k=0 but i don't know why? But if i use k=NULL, then it will not plot the resultant tree.
2002 Oct 24
2
glm and lrm disagree with zero table cells
I've noticed that glm and lrm give extremely different results if you
attempt to fit a saturated model to a dataset with zero cells. Consider,
for instance the data from, Agresti's Death Penalty example [0].
The crosstab table is:
, , PENALTY = NO
VIC
DEF BLACK WHITE
BLACK 97 52
WHITE 9 132
, , PENALTY = YES
VIC
DEF BLACK WHITE
BLACK 6 11
2007 Jan 22
1
OT: Optimum voice problems.
I'm trying to figure out if I'm the only one with these problems with them.
I recently had a few customers that switched to them because of the
price, of course that means that they have to use FXO ports, but it is
realy cheaper, so customers don't really care.
In any case, there are 2 issues that I can't get solved, and they are
not interested in helping.
1. When they tell you
2006 Nov 09
0
request for optimum setup configuration
hi,
I am required to take text/doc files uploaded to a share/directory in a
static ip, do some processing on this queue, convert the file format and
save the results in a directory for it to be downloaded (or I could
upload the same to another share/folder in another static ip).
volume of files is about 1-5 files/second of about 50KB to 100KB each
and the converting and delivery has to be in
2015 Aug 19
0
Optimum Block Size to use
On Wed, 19 Aug 2015, Jatin Davey wrote:
> Hi All
>
> We use CentOS 6.6 for our application. I have profiled the application and
> find that we have a heavy requirement in terms of Disk writes. On an average
> when our application operates at a certain load i can observe that the disk
> writes / second is around 2 Mbps (Average).
Initial thought is, do you really care? 2Mbps
2015 Aug 19
1
Optimum Block Size to use
On 8/19/2015 1:54 PM, John Hodrien wrote:
> On Wed, 19 Aug 2015, Jatin Davey wrote:
>
>> Hi All
>>
>> We use CentOS 6.6 for our application. I have profiled the
>> application and find that we have a heavy requirement in terms of
>> Disk writes. On an average when our application operates at a certain
>> load i can observe that the disk writes / second