Displaying 20 results from an estimated 2000 matches similar to: "Odds ratios from lrm plot"
2010 Dec 25
2
predict.lrm vs. predict.glm (with newdata)
Hi all
I have run into a case where I don't understand why predict.lrm and
predict.glm don't yield the same results. My data look like this:
set.seed(1)
library(Design); ilogit <- function(x) { 1/(1+exp(-x)) }
ORDER <- factor(sample(c("mc-sc", "sc-mc"), 403, TRUE))
CONJ <- factor(sample(c("als", "bevor", "nachdem",
2012 Jun 20
2
Odds Ratios in rms package
Hi,
I'm using the rms package to do regression analysis using the lrm
function. Retrieving odds ratios is possible using summary.rms. However,
I could not find any information on how exactly the odds ratios for
continuous variables are calculated. It doesn't appear to be the odds
ratio at 1 unit increase, because the output of summary.rms did not
match the coefficient's value.
E.g.
2010 Feb 06
4
Plot of odds ratios obtained from a logistic model
Hi all!
I am trying to develop a plot a figure in which I would like to show
the odds ratios obtained from a logistic model. I  have tried with the
dotplot option but no success. Could you help me? Is there any option
when modelling the logistic model in R?
Thank you in advance
2012 May 27
2
Unable to fit model using “lrm.fit”
Hi,
I am running a logistic regression model using lrm library and I get the
following error when I run the command:
mod1 <- lrm(death ~ factor(score), x=T, y=T, data = env1)
Unable to fit model using ?lrm.fit?
where score is a numeric variable from 0 to 6.
LRM executes fine for the following commands:
mod1 <- lrm(death ~ score, x=T, y=T, data = env1)
mod1<- lrm(death ~     
2017 Sep 14
3
Help understanding why glm and lrm.fit runs with my data, but lrm does not
Dear all,
I am using the publically available GustoW dataset.  The exact version I am using is available here: https://drive.google.com/open?id=0B4oZ2TQA0PAoUm85UzBFNjZ0Ulk
I would like to produce a nomogram for 5 covariates - AGE, HYP, KILLIP, HRT and ANT.  I have successfully fitted a logistic regression model using the "glm" function as shown below.
library(rms)
gusto <-
2010 Oct 01
6
Interpreting the example given by Frank Harrell in the predict.lrm {Design} help
Dear list,
I am relatively new to ordinal models and have been working through the example given by Frank Harrell in the predict.lrm {Design} help 
All of this makes sense to me, except for the responses, i,e how do i interpret them? i would be extremely grateful if someone could explain the results?
First i establish the date and model - 
> y <- factor(sample(1:3, 400, TRUE), 1:3,
2017 Sep 14
0
Help understanding why glm and lrm.fit runs with my data, but lrm does not
> On Sep 14, 2017, at 12:30 AM, Bonnett, Laura <L.J.Bonnett at liverpool.ac.uk> wrote:
> 
> Dear all,
> 
> I am using the publically available GustoW dataset.  The exact version I am using is available here: https://drive.google.com/open?id=0B4oZ2TQA0PAoUm85UzBFNjZ0Ulk
> 
> I would like to produce a nomogram for 5 covariates - AGE, HYP, KILLIP, HRT and ANT.  I have
2010 Apr 26
1
logical(0) response from lrm
What causes the error report:
logical(0)
to arise in the rms function lrm?
Here's my data:
But both the dependent and the independent variable seem fine...
 > str(AABB)
'data.frame':    1176425 obs. of  9 variables:
  $ sex     : int  1 1 0 1 1 0 0 0 0 0 ...
$ faint   : int  0 0 0 0 0 0 0 0 0 0 ...
Here's the simplified model and error
AABB$model1 < lrm (faint ~  sex)
2011 May 18
1
logistic regression lrm() output
Hi, I am trying to run a simple logistic regression using lrm() to calculate a 
odds ratio. I found a confusing output when I use summary() on the fit object 
which gave some OR that is totally different from simply taking 
exp(coefficient), see below:
> dat<-read.table("dat.txt",sep='\t',header=T,row.names=NULL)
> d<-datadist(dat)
> options(datadist='d')
2011 Jan 18
2
Baseline terms for lrm
Dear R-help and Prof. Harrell:
My question concerns the baseline state for continuous variable in lrm() 
within the RMS package.
I have a model which can be reduced to:
lrm(FT ~ rcs(V1, c(0, 1,5))
The model makes perfect sense if the baseline state is where V1>=5 but 
the model makes no sense if the baseline category is 0 (which I had 
expected).
Can someone point me to a reference, or
2017 Sep 14
1
Help understanding why glm and lrm.fit runs with my data, but lrm does not
Fixed 'maxiter' in the help file.  Thanks.
Please give the original source of that dataset.
That dataset is a tiny sample of GUSTO-I and not large enough to fit this
model very reliably.
A nomogram using the full dataset (not publicly available to my knowledge)
is already available in http://biostat.mc.vanderbilt.edu/tmp/bbr.pdf
Use lrm, not lrm.fit for this.  Adding maxit=20 will
2009 Sep 26
1
Summary/Bootstrap for Design library's lrm function
Can anyone tell me what I might be doing incorrectly for an ordinal
logistic regression for lrm?
 I cannot get R(2.9.1)to run either summary nor will it let me bootstrp to
validate.
### Y is a 5 value measure with a range from 1-5, the independent
variables are the same.  N=75 but when we knock out the NAs it comes down
to 51####
> lrm(formula = Y ~ permemp + rev + gconec + scorpstat, data =
2010 Aug 11
3
extracting the standard error in lrm
Hi,
I would like to extract the coefficients of a logistic regression
(estimates and standard error as well) in lrm as in glm with
summary(fit.glm)$coef
Thanks
David
2011 Apr 30
2
recommendation on B for validate.lrm () ?
I have a logistic regression model I'm trying to do k-fold cross validation
on.
The number of observations is approximately 550 and an event rate of about
30%
Does anyone have a recommendation for a B value to use for this data set?
--
View this message in context: http://r.789695.n4.nabble.com/recommendation-on-B-for-validate-lrm-tp3486200p3486200.html
Sent from the R help mailing list
2005 Jul 12
1
Design: predict.lrm does not recognise lrm.fit object
Hello
I'm using logistic regression from the Design library (lrm), then fastbw to
undertake a backward selection and create a reduced model, before trying to
make predictions against an independent set of data using predict.lrm with
the reduced model.  I wouldn't normally use this method, but I'm
contrasting the results with an AIC/MMI approach.  The script contains:
# Determine full
2003 Dec 05
3
Odds ratios for categorical variable
Dear R-users:
How does one calculate in R  the odds ratios for a CATEGORICAL predictor 
variable that has 4 levels.  I see r-help inquiries regarding odds ratios 
for what looked like a continuous predictor variable.  I was wondering how 
to get the pairwise odds ratios for comparisons of levels of a categorical 
predictor variable.  I can't seem to get the correct output using:
 >
2008 Apr 03
1
Design package lrm summary and factors
Hello, I have question regarding the lrm function and estimating the odds
ratio between different levels of a factored variable.
The following code example illustrates the problem I am having. I have a
data set with an outcome variable (0,1) and an input variable (A,B,C). I
would like to estimate the effect of C vs B, but when I perform the summary
I only get A vs B and A vs C, even though I
2004 Mar 22
2
Handling of NAs in functions lrm and robcov
Hi R-helpers
I have a dataframe DF (lets say with the variables, y, x1, x2, x3, ..., 
clust) containing relatively many NAs.
When I fit an ordinal regression model with the function lrm from the 
Design library:
model.lrm <- lrm(y ~ x1 + x2, data=DF, x=TRUE, y=TRUE)
it will by default delete missing values in the variables y, x1, x2.
Based on model.lrm, I want to apply the robust covariance
2009 Aug 29
3
lrm in Design
Hello everybody,
I am trying to do a logistic regression model with lrm() from the design
package. I am comparing to groups with different medical outcome which can
either be "good" or "bad". In the help file it says that lrm codes al
responses to 0,1,2,3, etc. internally and does so in alphabetical order. I
would guess this means bad=0 and good=1.
My question: I am trying to
2008 Oct 09
2
Singular information matrix in lrm.fit
Hi R helpers,
I'm fitting large number of single factor logistic regression models
as a way to immediatly discard factor which are insignificant.
Everything works fine expect that for some factors I get error message
"Singular information matrix in lrm.fit" which breaks whole execution
loop... how to make LRM not to throw this error and simply skip
factors with singularity