Displaying 20 results from an estimated 8000 matches similar to: "glm binomial logit - removing extra computations"
2010 Dec 17
1
[Fwd: adding more columns in big.matrix object of bigmemory package]
Hi,
With reference to the mail below, I have large datasets, coming from various
different sources, which I can read into filebacked big.matrix using library
bigmemory. I want to merge them all into one 'big.matrix' object. (Later, I
want to run regression using library 'biglm').
I am unsuccessfully trying to do this from quite some time now. Can you
please
2009 Jun 02
2
bigmemory - extracting submatrix from big.matrix object
I am using the library(bigmemory) to handle large datasets, say 1 GB,
and facing following problems. Any hints from anybody can be helpful.
_Problem-1:
_
I am using "read.big.matrix" function to create a filebacked big matrix
of my data and get the following warning:
> x =
read.big.matrix("/home/utkarsh.s/data.csv",header=T,type="double",shared=T,backingfile
2009 May 18
2
intermediate iterations of stepwise regression
Hi all,
I am performing a stepwise regression by running the "step" function on
an "lm" object. Now I want to save the intermediate iterations. I know
the argument trace=T will print it on the console, but I rather want to
assign it to some R object or may be output it in a CSV or text file.
Any help will be appreciated.
Regards
Utkarsh
2009 May 04
4
Splitting a vector into equal groups
Hi All,
I have vector of length 52, say, x=sample(30,52,replace=T). I want to
sort x and split into five *nearly equal groups*. Note that the
observations are repeated in x so in case of a tie I want both the
observations to fall in same group.
This seems a very common task to do, but still I couldn't find an R
function to do this. Any help would be highly appreciated.
Regards
Utkarsh
2009 Jul 03
2
bigglm() results different from glm()
Hi Sir,
Thanks for making package available to us. I am facing few problems if
you can give some hints:
Problem-1:
The model summary and residual deviance matched (in the mail below) but
I didn't understand why AIC is still different.
> AIC(m1)
[1] 532965
> AIC(m1big_longer)
[1] 101442.9
Problem-2:
chunksize argument is there in bigglm but not in biglm, consequently,
2009 Jun 30
4
R version-2.9.1 for Linux
Hi All,
I am currently using R version 2.8.1 on linux cent os 4.4 (i386) and
want to upgrade to version 2.9.1. It seems to me that version-2.9.1 is
it not for my OS.
Am I right?
Regards
Utkarsh
[[alternative HTML version deleted]]
2011 Aug 26
2
How to find the accuracy of the predicted glm model with family = binomial (link = logit)
Hi All,
When modeling with glm and family = binomial (link = logit) and response values of 0 and 1, I get the predicted probabilities of assigning to my class one, then I would like to compare it with my vector y which does have the original labels. How should I change the probabilities into values of zero and 1 and then compare it with my vector y to find out about the accuracy of my
2009 Nov 23
3
FUN argument to return a vector in aggregate function
Hi All,
I am currently doing the following to compute summary statistics of
aggregated data:
a = aggregate(warpbreaks$breaks, warpbreaks[,-1], mean)
b = aggregate(warpbreaks$breaks, warpbreaks[,-1], sum)
c = aggregate(warpbreaks$breaks, warpbreaks[,-1], length)
ans = cbind(a, b[,3], c[,3])
This seems unnecessarily complex to me so I tried
> aggregate(warpbreaks$breaks, warpbreaks[,-1],
2005 Jul 15
2
glm(family=binomial(link=logit))
Hi
I am trying to make glm() work to analyze a toy logit system.
I have a dataframe with x and y independent variables. I have
L=1+x-y (ie coefficients 1,1,-1)
then if I have a logit relation with L=log(p/(1-p)),
p=1/(1+exp(L)).
If I interpret "p" as the probability of success in a Bernouilli
trial, and I can observe the result (0 for "no", 1 for
2009 Jun 17
2
glm binomial logit
Hi All,
I am using "glm" function to build logistic regression. I noticed that glm
function glm function is computing many other statistics which are not
required for our analysis. As our dataset is very big and we have to run
logistic regression on several samples the run time drastically increases
if all those statistics are computed. Is these any way to skip computation
in glm
2009 Apr 30
2
problem in as.date
I never understood that why is the value returned by as.date function in
the library(survival) never matches with the description given in the
help file:
Following is the extract from ?as.date
Description:
Converts any of the following character forms to a Julian date:
8/31/56, 8-31-1956, 31 8 56, 083156, 31Aug56, or August 31 1956.
Usage:
as.date(x, order = "mdy", ...)
2008 Mar 03
1
using 'lrm' for logistic regression
Hi R,
I am getting this error while trying to use 'lrm' function with nine
independent variables:
> res =
lrm(y1994~WC08301+WC08376+WC08316+WC08311+WC01001+WC08221+WC08106+WC0810
1+WC08231,data=y)
singular information matrix in lrm.fit (rank= 8 ). Offending
variable(s):
WC08101 WC08221
Error in j:(j + params[i] - 1) : NA/NaN argument
Now, if I take choose only four
2017 Aug 10
0
Import selected columns from sas7bdat file
I had a look at this a while back and it didn't seem to be easy. The path of least resistance would seem to be to use SAS itself to create a data set with fewer columns, but of course that requires you to get access to SAS.
Otherwise, I think you'd have to modify sas7bdat::read.sas7bdat to drop unselected columns. That function is pure R code, so it might not be quite as hard as it
2017 Aug 10
1
Import selected columns from sas7bdat file
hi, the sas universal viewer might be a free, non-R way to convert a
sas7bdat file to non-proprietary formats, not sure if it's windows-only.
those other formats should be easier to import only a subset of columns
into R..
https://support.sas.com/downloads/browse.htm?fil=&cat=74
On Thu, Aug 10, 2017 at 7:42 AM, peter dalgaard <pdalgd at gmail.com> wrote:
> I had a look at this
2009 May 27
3
Defining functions - an interesting problem
I define the following function:
(Please don't wonder about the use of this function, this is just a
simplified version of my actual function. And please don't spend your
time in finding an alternate way of doing the same as the following does
not exactly represent my function. I am only interested in a good
explanation)
> f1 =
2009 Jul 14
2
SOS! error in GLM logistic regression...
Hi all,
Could anybody tell me what happened to my logistic regression in R?
mylog=glm(mytraindata$V1 ~ ., data=mytraindata, family=binomial("logit"))
It generated the following error message:
Error in model.frame.default(Terms, newdata, na.action = na.action,
xlev = object$xlevels) :
factor 'state1' has new level(s) AP
Thank you!
2006 Mar 27
1
Glm poisson
Hello,
I am using the glm model with a poisson distribution. The model runs
just fine but when I try to get the null deviance for the model of the
null degrees of freedom I get the following errors:
> null.deviance(pAmeir_1)
Error: couldn't find function "null.deviance"
> df.null(pAmeir_1)
Error: couldn't find function "df.null"
When I do:
>
2009 Feb 25
1
how to label the branches of a tree
Hi,
I am using rpart package to fit classification trees.
library(rpart)
fit <- rpart(Kyphosis ~ Age + Number + Start, data=kyphosis)
plot(fit,uniform=T)
text(fit, use.n=TRUE)
But I am unable to label the branches (not the nodes) of the tree. Can somebody help me out in this?
Thank you,
Regards
Utkarsh Singhal | Amba Research
Ph +91 80 3980 8017 | Mob +91 99 0295 8815
2017 Aug 10
2
Import selected columns from sas7bdat file
Hello everyone,
I want to import data from huge sas files with 100s of columns. The good
thing is that I am only interested in a few selected columns. Is there any
way to do that without loading the full dataset.
I have tried two functions: (1) read.sas7bdat *[from library 'sas7bdat']*,
and (2) read_sas *[from library 'haven']. *But couldn't find what I am
looking for.
Best
2009 Jun 16
1
Testing if all elements are equal in a vector/matrix
Hi All,
There are several replies to the question below, but I think there must
exist a better way of doing so.
I just want to check whether all the elements of a vector are same. My
vector has one million elements and it is highly likely that there are
distinct elements in the first few itself. For example:
> x = c(1,2,rep(1,100000))
I want the answer as FALSE, which is clear from the