Displaying 20 results from an estimated 5000 matches similar to: "Units"
2004 Oct 15
1
power in a specific frequency band
Dear R users
I have a really simple question (hoping for a really simple answer :-):
Having estimated the spectral density of a time series "x" (heart rate
data) with:
x.pgram <- spectrum(x,method="pgram")
I would like to compute the power in a specific energy band.
Assuming that frequency(x)=4 (Hz), and that I am interested in the band
between f1 and f2, is the
2009 May 19
2
Getting lm() to work with a matrix
Hi
I'm fairly new to R and am trying to analyse some large spectral datasets
using stepwise regression (fairly standard in this area). I have a field
sampled dataset, of which a proportion has been held back for validation. I
gather than step() needs to be fed a regression model and lm() can produce a
multiple regression. I had thought something like:
spectra.lm <-
2009 Mar 03
3
PLS regression on near infrared (NIR) spectra data
Dear collegues,
I´ ve worked with near infrared (NIR) spectroscopy to assess chemical,
physical, mechanical and anatomical properties of wood.
I use "The Unscrambler" software to correlate the matrix of dependent
variables (Y) with the matrix of spectral data (X) and I would like to
migrate to R. The matrix of spectral variables is very large (2345 columns
and n lines, where n =
2010 Jun 08
2
problem with if else statement
Dear colleagues,
What did I not understand ?
->my intention
I want to create a new variable:
In plain language:
If someone is taking anithypertensive treatment (med.hyper==1)
table(med.hyper)
med.hyper
0 1
472 97
I want to subtract 5 mmHg (rr.dia.2m-5) from the measured diastolic
blood pressure (rr.dia.2m)
if not treated - the value of the measured diastolic blood pressure
should
2018 Jan 03
1
summary.rms help
Dear All,
using the example from the help of summary.rms
library(rms)
n <- 1000 # define sample size
set.seed(17) # so can reproduce the results
age <- rnorm(n, 50, 10)
blood.pressure <- rnorm(n, 120, 15)
cholesterol <- rnorm(n, 200, 25)
sex <- factor(sample(c('female','male'), n,TRUE))
label(age) <- 'Age'
2018 Apr 18
3
Problem with regression line
Hello,
I am trying to graph a regression line using the followings:
Age <- c(39, 47, 45, 47, 65, 46, 67, 42, 67, 56, 64, 56, 59, 34, 42, 48, 45,
17, 20, 19, 36, 50, 39, 21, 44, 53, 63, 29, 25, 69)
BloodPressure <- c(144, 220, 138, 145, 162, 142, 170, 124, 158, 154, 162,
150, 140, 110, 128, 130, 135, 114, 116, 124, 136, 142, 120, 120, 160, 158,
144, 130, 125, 175)
SimpleLinearReg1=lm(Age ~
2007 Nov 21
1
Different freq returned by spec.ar() and spec.pgram()
Dear list,
I've recently become interested in comparing the spectral estimates
using the different methods ("pgram" and "ar") in the spectrum()
function in the stats package.
With many thanks to the authors of these complicated functions, I
would like to point out what looks to me like a bit of an
inconsistency -- but I would not be surprised if there is good
reasoning
2002 Sep 13
1
design package (plot problems)
Hi,
just making some experiments with
design library i get an error if
i want plot(fit) - show below from
onlineHelp !?
..perhaps is here another mask problem?, but
label from xtable which was my first problem
is now off !
Thanks for advance & regards,
Christian
$ n <- 1000 # define sample size
$ set.seed(17) # so can reproduce the results
$ age <- rnorm(n, 50, 10)
2018 Apr 18
0
Problem with regression line
Hi, Anne,
assign Age and Bloodpressure in the correct order
to the axes in your call to plot as in:
plot(y = Age, x = BloodPressure)
abline(SimpleLinearReg1)
Hth -- Gerrit
---------------------------------------------------------------------
Dr. Gerrit Eichner Mathematical Institute, Room 212
gerrit.eichner at math.uni-giessen.de Justus-Liebig-University Giessen
Tel:
2008 May 29
2
Troubles plotting lrm output in Design Library
Dear R-helpers,
I'm having a problem in using plot.design in Design Library. Tho
following example code produce the error:
> n <- 1000 # define sample size
> set.seed(17) # so can reproduce the results
> age <- rnorm(n, 50, 10)
> blood.pressure <- rnorm(n, 120, 15)
> cholesterol <- rnorm(n, 200, 25)
> sex <-
2011 Jul 11
1
Spectral Coherence
Greetings,
I would like to estimate a spectral coherence between
two timeseries. The stats : spectrum() returns a coh matrix
which estimates coherence (squared).
A basic test which from which i expect near-zero coherence:
x = rnorm(500)
y = rnorm(500)
xts = ts(x, frequency = 10)
yts = ts(y, frequency = 10)
gxy = spectrum( cbind( xts, yts ) )
plot( gxy $ freq, gxy $
2005 Aug 22
1
How to add legend of plot.Design function (method=image)? (if (!.R.) )
Hi,
When running
z <- plot(fit, age=NA, cholesterol=NA, perim=boundaries, method='image')
Legend(z, fun=plogis, at=qlogis(c(.01,.05,.1,.2,.3,.4,.5)),
zlab='Probability')
And after pointing the cursor to the plot() screen in R, I obtain the
following message:
Using function "locator(2)" to place opposite corners of image.legend
Error in
2009 Dec 01
1
An R vs. SAS Discrepancy: How do I determine which is correct?
I was messing around with some data in R and SAS (the reason is
unimportant) fitting a multiple linear regression and got a
curious discrepancy. The data set is too big to post, but if
someone wants it, I can send it.
So, here are the (partial) results:
From R:
Coefficients:
Estimate Std. Error t value Pr(>|t|)
(Intercept) 61.11434 1.48065 41.275 < 2e-16 ***
sexWomen
2010 Aug 14
1
How to add lines to lattice plot produced by rms::bplot
I have a plot produced by function bplot (package = rms) that is
really a lattice plot (class="trellis"). It is similar to this plot
produced by a very minor modification of the first example on the
bplot help page:
requiere(rms)
n <- 1000 # define sample size
set.seed(17) # so can reproduce the results
age <- rnorm(n, 50, 10)
blood.pressure <- rnorm(n, 120,
2012 Dec 07
3
[Bridge] [PATCH net-next v4] bridge: export multicast database via netlink
From: Cong Wang <amwang at redhat.com>
V4: remove some useless #include
some coding style fix
V3: drop debugging printk's
update selinux perm table as well
V2: drop patch 1/2, export ifindex directly
Redesign netlink attributes
Improve netlink seq check
Handle IPv6 addr as well
This patch exports bridge multicast database via netlink
message type RTM_GETMDB.
2011 Feb 11
4
When is *interactive* data visualization useful to use?
Hello all,
Before getting to my question, I would like to apologize for asking this
question here. My question is not directly an R question, however, I still
find the topic relevant to R community of users - especially due to only *
partial* (current) support for interactive data visualization (see here:
http://cran.r-project.org/web/views/Graphics.html were with iplots we are
waiting for
2006 Oct 09
1
windows doesn't show groups in security tab of file properties
Hello,
I've a Samba 3.0.23c-SerNet-Debian PDC (no BDC or anything) connected to
OpenLDAP. I thought it would work smoothly, I didn't discover any
problems until today.
I'am trying to create a ntconfig.pol with poledit, but it doesn't show
me any groups to add to the policy. I can see all the users by the way.
To eleminate a poledit problem I used the security tab (in german
2018 Apr 18
1
Problem with regression line
Hi Anne,
I would suggest to change the linear model to lm(BloodPressure~Age), as
this model makes more sense in biological means (you would assume that
age influences pressure, not vice versa) and also obeys the statistical
assumption of weak exogeneity, that age can be measured without error,
at least compared to error-prone bp measures.
Cheers
Am 18.04.2018 um 16:07 schrieb Gerrit Eichner:
2009 Aug 09
2
floating point
On Aug 7, 2009, at 21:48, Didier Dambrin wrote:
> FLAC doesn't preserve every chunk? I thought it did. I only gave a
> quick try
> but it seemed to have preserved even the most obscure chunks.
> Let me check: it even seems to preserve "MIDI note associated to
> marker",
> which is a very unknown metadata used by SoundForge (& even defined
> in a
>
2012 Jun 09
1
combining different types of graphics (scatterplots, boxplots) using lattice
Dear R users:
I have a continuous outcome variable and four predictors, two continuous and
two dichotomous. i would like to use the lattice plot to create scatter
plots for the continuous predictors and boxplots for the dichotomous
predictors.
with 4 continuous variables, this is what i have been doing:
trial = rbind (
cbind ( cimt$ant.mean, cimt$age, 1 ),
cbind ( cimt$ant.mean, cimt$sbp, 2 ),