Displaying 20 results from an estimated 400 matches similar to: "Profile confidence intervals and LR chi-square test"
2005 Jun 14
1
Matrix stability problem
Hello,
This is not a problem with R, the calculated results are mathematically
correct. This a matrix stability problem. Because of measuring errors, my
matrix solution is a bit off.
Here is what my equations look like:
A11 x11+A12 x12 +A13 x13 = b1
A21 x21+A22 x21 +A23 x23 = b2
A31 x31+A32 x31 +A33 x33 = b3
A is a reading, X is a measured weight, and b is total. The 3 experiments
give
2011 May 01
1
Longitudinal data with non-randomized subjects
Dear List,
I have a theoretical question related to epidemiological data analysis:
If the treatment status (tx = 0,1) changes over time for the patients in a non-randomized cohort, is there a way to estimate the treatment effect?
(i.e., after joining the study, some patients may have to wait for a period of time before receiving the treatment, i.e., the situation of patient with id == 2 for the
2006 Mar 11
1
Non-linear Regression : Error in eval(expr, envir, enclos)
Hi..
i have an expression of the form:
model1<-nls(y~beta1*(x1+(k1*x2)+(k1*k1*x3)+(k2*x4)+(k2*k1*x5)+(k2*k2*x6)+(k3*x7)+(k3*k4*x8)+(k3*k2*x9)+(k3*k3*x10)+ (k4*x11)+(k4*k1*x12)+(k4*k2*x13)+(k4*k3*x14)+(k4*k4*x15)+(k5*x16)+(k5*k1*x17)+(k5*k2*x18)+(k5*k3*x19)+
2008 May 19
2
Help on nested FOR loops
I am new to more radical programming in R. I am trying to write a nested 'for' loop to produce output that takes subscripts like:
for i taking values 1,2,3,4,5 and
j taking values 1,2,3
I want to output for a computation using the combination values of i and j a value x like this;
i j x
1 1 x11
1 2 x12
1 3 x13
2 1 x21
2 2 x22
2 3 x23
3 1 x31
3 2 x32
2004 Sep 21
3
how to take this experiment with R?
How about:
x <- data.frame(matrix(rnorm(1550),c(50,31)))
model <- step(lm(x[,1] ~ as.matrix(x[,2:31])))
--Matt
-----Original Message-----
From: r-help-bounces at stat.math.ethz.ch
[mailto:r-help-bounces at stat.math.ethz.ch]On Behalf Of rongguiwong
Sent: Monday, September 20, 2004 20:52 PM
To: r-help at stat.math.ethz.ch
Subject: [R] how to take this experiment with R?
This message uses
2011 Aug 20
2
a Question regarding glm for linear regression
Hello All,
I have a question about glm in R. I would like to fit a model with glm function, I have a vector y (size n) which is my response variable and I have matrix X which is by size (n*f) where f is the number of features or columns. I have about 80 features, and when I fit a model using the following formula,?
glmfit = glm(y ~ x1 + x2 + x3 + x4 + x5 + x6 + x7 + x8 + x9 + x10 + x11 + x12 + x13
2018 Mar 14
2
truncation/rounding bug with write.csv
I don't see the issue here. It would be helpful if people would report
their sessionInfo() when reporting whether or not they see this issue.
Mine is
> sessionInfo()
R version 3.4.3 (2017-11-30)
Platform: x86_64-pc-linux-gnu (64-bit)
Running under: Arch Linux
Matrix products: default
BLAS/LAPACK: /usr/lib/libopenblas_haswellp-r0.2.20.so
locale:
[1] LC_CTYPE=en_US.UTF-8
2012 Nov 28
1
Help setting optimization problem to include more constraints
Dear R-helpers,
I am struggling with an optimization problem at the moment and decided to
write the list looking for some help. I will use a very small example to
explain what I would like to. Thanks in advance for your help.
We would like to distribute resources from 4 warehouses to 3 destinations.
The costs associated are as follows:
Destination
>From 1 2 3 Total
2006 Nov 06
5
memory issues with new release (PR#9344)
Full_Name: Derek Elmerick
Version: 2.4.0
OS: Windows XP
Submission from: (NULL) (38.117.162.243)
hello -
i have some code that i run regularly using R version 2.3.x . the final step of
the code is to build a multinomial logit model. the dataset is large; however, i
have not had issues in the past. i just installed the 2.4.0 version of R and now
have memory allocation issues. to verify, i ran
2004 May 11
1
calling data frames
Dear List,
I've around 1000 *.txt files, I've generate with other software.
I've now done the following code (below).
My question is how can I automate this (with do.call () ?), so it could be
done for all the *.txt files.
Thanks in advance,
Rog??rio
names<- list.files()
file <- "BLU_Var_%04d.txt"
for(i in 1:1000){
2018 Mar 14
2
truncation/rounding bug with write.csv
To my surprise, I can confirm on Windows 10 using R 3.4.3 . As tail is not
recognized by Windows cmd, I replaced with:
system('powershell -nologo "& "Get-Content -Path temp.csv -Tail 1')
The last line shows only 7 digits after the decimal, whereas the first have
15 digits after the decimal. I agree with Dirk though, 1.6Gb csv files are
not the best way to work with
2010 May 11
1
Help with Names
Hi - a newbie question, if someone can please help....
I want to change X1, X2,,.....to X.1 X.2 etc in the names below. I am using
the Principal Component Regression function (pcr) and it seems to want it
this way
> datap3.pcr <- pcr(water ~ X, 10, data = datap3, Validation ="cv")
Error in model.frame.default(formula = water ~ X, data = datap3) :
invalid type (list) for
2018 Mar 14
2
truncation/rounding bug with write.csv
Hello, I have looked on https://www.r-project.org/bugs.html , but it seems
that this is the only way to do it.
The issue is that the precision used by write.csv is on consistant for big
files. See the following code:
First I create a large dataframe filled with random uniform values. Then I
write it to .csv and print out the first and last lines.
df = data.frame(replicate(100, runif(1000000,
2002 Jul 02
0
pam and openssh
All,
I'm trying to use PAM to replicate the authorized user functionality in
commercial ssh. In the past, I've patched openssh to do this, but I think
that solution is fairly ugly (and requires me to patch with each new
release of openssh which is really bad).
I want to do this:
0. use openssh for all communication with this machine.
1. check a user's identity using their
2012 Jun 15
0
Flexmix package
Hi,
I am using the package "flexmix" and would like get some assistance.
I am trying to run two equations jointly
Y1=X1B+E1
Y2=X2G+E2
So that I have X and Y in a matrix format and would like to run the latent
class model using flexmix.
Though, my problem here is that Flexmix automatically generates intercepts.
I have intercept for both of the equations that my X matrix looks like
2013 Apr 12
2
model frame and formula mismatch in model.matrix()
Hello everyone,
I am trying to fit the following model
All X. variables are continuous, while the conditions are categoricals.
model <- lm(X2
2018 Mar 14
0
truncation/rounding bug with write.csv
My apologies for not including sessionInfo(), and I'm a bit angry at myself
for that. Retrying in a fresh session of R, I get different results. More
specifically, I get the expected result where accuracy is the same in the
first and the last line. As I didn't include my sessionInfo() in my
previous mail, I can't figure out why I now have a different result. So I'm
positive
2011 Jun 01
1
as.character limits length of result for formula
If you want a character representation of a long formula (or
a formula with long names), you can use:
as.character(my.formula)
However restriction on length of an as.character result
returns only the beginning of a long formula, and without comment.
In most cases, the following expression provides the complete
result:
paste(my.formula[[2]], " ~ ",
2009 Jun 24
2
change the height or scale of the y axis
Hallo, All,
I have a question about changing the height or scale of the y axis. When I
use following two R codes, I can get two plots. Please look at the y axes,
the number of indices (x1, x2, ?) on the y axis in the first plot is smaller
than that in the second plot, and hence the space between any two indices in
the first plot is wider than that in the second plot. As the number of
indices
2012 May 25
2
Query about creating time sequences
Hi All,
I have a query about time based sequences. I know such questions have been
asked a lot on forums, but I couldnt find the exact thing that I was
looking for.
I want to create a time-based sequence which will mimic the trading window
AND would span multiple days. Something like below:
"2011-01-03 09:15:00 IST"
"2011-01-03 09:15:01 IST"
....
....
....
"2011-01-03