Displaying 20 results from an estimated 1000 matches similar to: "van der waerden test"
2004 Mar 06
2
normal scores test
Hello,
I need help in performing a Van_der_Waerden normal scores test in R. I
have two arrays of scores(final on therapy scores from drug and placebo) and
want to use the normal scores procdeure to test for significance.
(observations are unequal in number - due to dropouts). Could you please help
me out with the coding or let me know if there is a package that can be used
(for example,
2003 Aug 19
9
Variance Computing- - HELP!!!!!!!!!!!!!!!!!!
Hello,
I am running a few simulations for clinical trial anlysis. I want some help
regarding the following.
We know trhat as the sample size increases, the variance should decrease, but
I am getting some unexpected results. SO I ran a code (shown below) to check
the validity of this.
large<-array(1,c(1000,1000))
small<-array(1,c(100,1000))
for(i in
2008 May 23
1
van der Corput sequences
In package fOptions, there are functions that generate
Halton sequences.
The van der Corput sequence for base 2 is a particular case
of the Halton sequence generated by:
n <- 8 # anything here...
x <- runif.halton(n, 1)
In fact, x <- runif.halton(n, dim) will generate the van der Corput
sequences for the base b as the i-th prime number in x[,i].
(in other words, if I want the van der
2013 Sep 01
0
Question About Markov Models
Dear All,
I am a bit struggling with the many packages for Markov models available
in R.
Apologies for now posting a code snippet, but I am looking for some
guidance here.
Please consider a set like the one below (which you can get with
data<-read.csv('http://dl.dropboxusercontent.com/u/5685598/data_table.csv')
).
ID therapy age1 age2 EFS
7308 ormo_lunga 78
2012 Oct 22
0
Lattice to ggplot2: Reference graphics across facets
Hi,
I'm playing with moving some of my lattice graphics into ggplot2, and I'd
like to ask how to achieve a couple of things, both of which are fully
illustrated in self-contained code (and mostly minimal, although that left
quite a bit) following this written description.
1. I quite often like to use a 'ghosted' reference across facets - for
example, in my example program below,
2009 Jan 20
1
generalizing expand.table: table -> data.frame
In
http://tolstoy.newcastle.edu.au/R/e2/help/06/10/3064.html
a method was given for converting a frequency table to an expanded data
frame representing each
observation as a set of factors. A slightly modified version was later
included in the NCStats package,
only on http://rforge.net/ (and it has too many dependencies to be useful).
I've tried to make it more general, allowing an input
2012 Jan 03
0
Job opportunity in AMSTERDAM: ANALYSIS OF NGS CANCER DATA
COMPUTATIONAL ANALYSIS OF NEXT GENERATION SEQUENCE DATA
(http://bioinformatics.nki.nl/vacancies.php)
THREE BIOINFORMATICS POSITIONS
PROJECT OUTLINE
Genomic alterations are major determinant of responses to (targeted) therapies in cancer. In fact, the best positive and negative predictors of responses to targeted therapies are alterations in kinases or their direct downstream effectors. To
2005 May 15
0
Seeking friend for life (not)
I'll take a risk following Uwe's wonderful response to that advert.
I'm looking for someone, perhaps particularly a stats student, who
might want to do a piece of work with me on using R to present and
analyse routine data that psychotherapists might submit on a cgi-bin
interface and perhaps cross-referencing that against some largish
referential data to which I have access.
2007 Dec 04
2
Learning to do randomized block design analysis
We just studied randomized block design analysis in my statistics class,
and I'm trying to learn how to do them in R. I'm trying to duplicate a
case study example from my textbook [1]:
> # Case Study 13.2.1, page 778
> cd <- c(8, 11, 9, 16, 24)
> dp <- c(2, 1, 12, 11, 19)
> lm <- c(-2, 0, 6, 2, 11)
> table <- data.frame(Block=LETTERS[1:5], "Score
2010 Jul 22
1
gam() and contrast
Dear All,
I met problems when doing contrast and now really need some help in the
model below:
Fit=gam(y~treat+SEQUENCE+PERIOD+SEX+s(x),data=dat,
random=list(SUBJID=~1),correlation=corAR1(form=~1|SUBJID))
And error message keeps coming out when I want to compare the differences
between treatments:
Diff=contrast(Fit,
list(treat=treatment[-placebo.pos]),list(treat="Placebo"),
2007 May 14
1
Nicely formatted summary table with mean, standard deviation or number and proportion
Dear all,
The incredibly useful Hmisc package provides a method to generate
summary tables that can be typeset in latex. The Alzola and Harrell book
"An introduction to S and the Hmisc and Design libraries" provides an
example that generates mean and quartiles for continuous variables, and
numbers and percentages for count variables: summary() with method =
'reverse'.
I
2011 Oct 03
1
Assigning factor names to interaction plot
Hi everyone,
I have the following problem:
I have three variables, 'group', 'city' and 'pressure'
There is an interaction effect between group and city and I'd like to show
this in an interaction plot:
interaction.plot(group, city, pressure, type="b",
col= c(1:2),
leg.bty="o", leg.bg="blue", lwd=1,
2002 May 27
1
nlme cross-over and fixed nested
I have problem getting the concept of a nested fixed variable into the nlme
scheme. I fear the question is very stupid. In the past I had asked this
before, and never got a reply (in other cases, the response was within
hours). I also checked the S-list, where several similar enquiries of other
people are orphaned.
We have a cross-over design, where patient are treated two weeks with
placebo,
2009 Feb 27
2
Adjusting confidence intervals for paired t-tests of multiple endpoints
Dear R-users,
In a randomized placebo-controlled within-subject design, subjects recieved
a psycho-active drug and placebo. Subjects filled out a questionnaire
containing 15 scales on four different time points after drug
administration. In order to detect drug effects on each time point, I
compared scale values between placebo and drug for all time conditions and
scales, which sums up to
2007 Sep 27
1
windows device transparency issue
I read in a thread in r-help today that the windows device in 2.6 supports
transparency, so I tried an example and had some issues. The density plots
should be filled with transparent color in the following example (similar to
the points), however the color is "fully" transparent. This works in the
Cairo device, but not in the windows device.
Thanks,
--Matt
Matt Austin
2007 Jun 15
1
complex contrasts and logistic regression
Hi,
I am doing a retrospective analysis on a cohort from a designed trial,
and I am fitting
the model
fit<-glmD(survived ~ Covariate*Therapy + confounder,myDat,X=TRUE,
Y=TRUE, family=binomial())
My covariate has three levels ("A","B" and "C") and therapy has two
(treated and control), confounder is a continuous variable.
Also patients were randomized to
2004 Mar 10
1
Rank Simulations - Test statistic Help
Hi all,
I am a biostatistician and I have developed my own
ranking system for clinical data. I would like to test
the efficiency of it w.r.t. to other ranking systems.
I would like to simulate the data and after assigning
ranks to my observed scores(after neglecting
dropouts), observe the type I error. If I want to do a
Kruuskal Wallis type of test, what test statistic
should I use to test for a
2007 May 17
2
How to analyse simple study: Placebo-controlled (2 groups) repeated measurements (ANOVA, ANCOA???)
Hallo!
I have two groups (placebo/verum), every subject is measured at 5 times, the first time t0 is the baseline measurement, t1 to t4 are the measurements after applying the medication (placebo or verum). The question is, if there is a significant difference in the two groups and how large the differnce is (95% confidence intervals).
Let me give sample data
# Data
2008 Mar 14
2
problems creating data frames
I am having two problems creating data frames that I have solutions, but
they really seem like kludges and I assume I just don't understand the
proper R way of doing things.
The first situation is I have an set of uneven data vectors. When I try to
use them to create a data frame I would like the bottoms of them padded with
NAs, without explicitly specifying that. When I do:
anxiety.data =
2008 Jul 02
1
auto.key in xyplot in conjunction with panel.text
All,
I can't seem to get auto.key to work properly in an xyplot that is employing
panel.text. Specifically, I often change the default grouping colors then
use auto.key accordingly, but for some reason the same functionality isn't
working for this different type of plot. Any help much appreciated.
Cheers,
David
library("lattice")
dat = data.frame( Y = c(rnorm(18,1),