Displaying 20 results from an estimated 10000 matches similar to: "A easy way to write formula"
2006 Apr 28
4
stepwise regression
Dear all,
I have encountered a problem when perform stepwise regression.
The dataset have more 9 independent variables, but 7 observation.
In R, before performing stepwise, a lm object should be given.
fm <- lm(y ~ X1 + X2 + X3 + X11 + X22 + X33 + X12 + X13 + X23)
However, summary(fm) will give:
Residual standard error: NaN on 0 degrees of freedom
Multiple R-Squared: 1, Adjusted
2010 Jan 15
1
Best method
Hi,
I would like to ask for advice about best statistics method for
my problem.
I was done questionnaire about headache.
My data are:
Y - frequency of symptoms occur - times per month in range <0..30>
(where 30 is daily and zero for never)
and independent variables:
X1 - sex - category {M,F}
X2 - age - linear value
X3 - type of work {administrative, manual, ...}
...
Which model is
2007 Nov 19
4
sequence of vectors
Dear All,
I wonder if there is any R function to generate a sequence of vectors from existing ones. For example:
x 1<- c(1,2,3)
x2 <- c(4,5)
x3 <- c(6,7,8)
The desired output is a list of all 3*2*3 = 18 possible combinations of elements of x1,x2 and x3. One element for example is (1,4,6).
Many thanks in advance,
Bernard
2010 Jun 29
5
More than two font in a plot
Hi there,
I am a Chinese R user. I hope to display Chinese character in a plot,
and than save it in PostScript format. I have read the article titled
"Non-Standard Fonts in PostScript and PDF Graphics", especially the
section about CJK fonts. I also tried the code:
> pdf("chinese.pdf", width=3, height=1)
> grid.text("\u4F60\u597D", y=2/3,
2018 Feb 20
2
Take the maximum of every 12 columns
Don't do this (sorry Thierry)! max() already does this -- see ?max
> x <- data.frame(a =rnorm(10), b = rnorm(10))
> max(x)
[1] 1.799644
> max(sapply(x,max))
[1] 1.799644
Cheers,
Bert
Bert Gunter
"The trouble with having an open mind is that people keep coming along and
sticking things into it."
-- Opus (aka Berkeley Breathed in his "Bloom County" comic
2018 Feb 20
0
Take the maximum of every 12 columns
The maximum over twelve columns is the maximum of the twelve maxima of
each of the columns.
single_col_max <- apply(x, 2, max)
twelve_col_max <- apply(
matrix(single_col_max, nrow = 12),
2,
max
)
ir. Thierry Onkelinx
Statisticus / Statistician
Vlaamse Overheid / Government of Flanders
INSTITUUT VOOR NATUUR- EN BOSONDERZOEK / RESEARCH INSTITUTE FOR NATURE
AND FOREST
Team Biometrie
2018 Feb 20
5
Take the maximum of every 12 columns
Dear all,
I have monthly data in wide format, I am only providing data (at the bottom
of the email) for the first 24 columns but I have 2880 columns in total.
I would like to take max of every 12 columns. I have taken the mean of
every 12 columns with the following code:
byapply <- function(x, by, fun, ...)
{
# Create index list
if (length(by) == 1)
{
nc <- ncol(x)
2012 Aug 30
1
path analysis help
Hi there,
I searched R-help list with "path analysis" as keyword, and learn that
sem package can do it. However, I don't figure out a way to construct
the model for the path diagram as Fig. 1. in Huang et al. (2002)[1].
I try the following code:
huang.cor <- readMoments(diag=FALSE, names=c('x1', 'x2', 'x3', 'y'))
0.76
0.91 0.72
0.94 0.77 0.83
2009 Dec 15
2
Instrumental Variables Regression
Hi there,
I hope to build a model Y ~ X1 + X2 + X3 + X4 with X1 has two
instrumental variable A and B, and X2 has one instrumental variable A. I
have searched the R site and mailling list, and known that the tsls()
from sem package and ivreg() from AER package can deal with instrumental
variable regression, however, I don't know how to formula the model.
Any suggestion will be really
2010 Jun 30
2
plain text in Chinese can not be set
Hi there,
According to ?par, 'font' is an integer which specifies which font to
use for text, that 1 corresponds to plain text (the default), 2 to bold
face, 3 to italic and 4 to bold italic.
When I test Chinese character in pdf(), I found that 1 to bold face, 2
to italic, 3 to bold italic, 4 to symbol. and I don't find how to set
plain text. In the following code, the font to use
2018 Feb 20
0
Take the maximum of every 12 columns
Thank you for your kind replies. Maybe I was not clear with my question (I
apologize) or I did not understand...
I would like to take the max for X0...X11 and X12...X24 in my dataset. When
I use pmax with the function byapply as in
byapply(df, 12, pmax)
I get back a list which I cannot convert to a dataframe. Am I missing
something? Thanks again!
Sincerely,
Milu
2009 Jun 29
5
Help
HiĀ group,
I found a module for adaptive kernel density estimation for Stata users, but unfortunetly I don't have access to Stata, can I find a similar approach using R?
Thank u so much 4 ur time.
[[alternative HTML version deleted]]
2011 Oct 22
1
Does R has a similar way as DATA in SPSS?
Hi there,
In SPSS, small piece of data can be input as following:
DATA LIST LIST /x1 x2 x3 x4 x5 .
BEGIN DATA
5700 12.8 2500 270 25000
1000 10.9 600 10 10000
3400 8.8 1000 10 9000
3800 13.6 1700 140 25000
4000 12.8 1600 140 25000
8200 8.3 2600 60 12000
1200 11.4 400 10 16000
9100 11.5 3300 60 14000
9900 12.5 3400 180 18000
9600 13.7 3600 390 25000
2008 Feb 12
4
How to run one-way anova R?
En innebygd og tegnsett-uspesifisert tekst ble skilt ut...
Navn: ikke tilgjengelig
Nettadresse: https://stat.ethz.ch/pipermail/r-help/attachments/20080212/d6012c8f/attachment.pl
2008 Sep 15
4
How to draw a plot like this?
Hi there,
I hope to draw a plot like this:
http://www.sg-chem.net/swizard/Ru-bqdi-spectra.gif
is it possible to draw it using R?
thanks for any suggestions.
regards,
Jinsong
2008 Jul 26
2
response surface analysis
Hi,
Is there a package that could do response surface analysis equivalent to
SAS RSREG procedure? Thanks!
Regards,
Jinsong
2006 Apr 06
2
Help on hypothesis testing
Hi,
I hope to use R to perform some hypothesis testing, such as t.test() and var.test().
However, I don't find a function that could do test on means with variance known
(i.e., u test or z test in some textbook), and a function that could do test on
variances of normal distribution (i.e. chi-squared test).
Thanks in advance for any hints.
Best wishes,
Jinsong
2008 Sep 06
1
Help use try function with boot
Hi R users,
Is is possible for me to use the try function with boot? I would to do
the bootstraping with a nonlinear model(it works well when R < 1000).
But it does not work very well (when R is large) thus I try to use
"try" to resolve. I put the try function in two cases:
case1: put the try in front of the boot
> c1.try<-try(boot(c1data, statistic = c1.fun,
2010 Sep 02
1
nlme formula from model specification
Dear R-community,
I'm analysing some noise using the nlme-package. I'm writing in order
to get my usage of lme verified.
In practise, a number of samples have been processed by a machine
measuring the same signal at four different channels. I want to model
the noise. I have taken the noise (the signal is from position 1 to
3500, and after that there is only noise).
My data looks like
2006 May 06
3
probit analysis
Dear all,
I have a very simple set of data and I would like to analyze them
with probit analysis.
dose event trial
0.0 3 15
1.1 4 15
1.3 4 15
2.0 3 15
2.2 5 15
2.8 4 15
3.7 5 15
3.9 9 15
4.4 8 15
4.8 11 15
5.9 12 15
6.8 13 15
The dose should be transformed with log10().
I use glm(y ~ log10(dose), family=binomial(link=probit)) to
do probit analysis, however, I have to exclude the