Displaying 20 results from an estimated 4000 matches similar to: "Expressions in lattice conditional variables"
2011 May 04
1
hurdle, simulated power
Hi all--
We are planning an intervention study for adolescent alcohol use, and I
am planning to use simulations based on a hurdle model (using the
hurdle() function in package pscl) for sample size estimation.
The simulation code and power code are below -- note that at the moment
the "power" code is just returning the coefficients, as something isn't
working quite right.
The
2012 Sep 16
1
Sub- or superscript in factorial variable - possible?
Hello R-users,
I would like to use subscript in chemical formulas for the different
treatments in a boxplot.
Fot title, xlab and ylab sub- and superscript is no problem, but for the
different treatments of the following example I cannot get subscript.
Example:
weight <- c(6,5,7,2,7,3,9,4,2,7,8,9,2,3,4,5)
treatments <- as.factor(rep(c('Control',
2006 Aug 24
1
how to constrast with factorial experiment
Hello, R users,
I have two factors (treat, section) anova design experiment where
there are 3 replicates. The objective of the experiment is to test if
there is significant difference of yield between top (section 9 to 11)
and bottom (section 9 to 11) of the fruit tree under treatment. I
found that there are interaction between two factors. I wonder if I
can contrast means from levels of
2008 Oct 15
2
Network meta-analysis, varConstPower in nlme
Dear Thomas Lumley, and R-help list members,
I have read your article "Network meta-analysis for indirect treatment
comparisons" (Statist Med, 2002) with great interest. I found it very
helpful that you included the R code to replicate your analysis;
however, I have had a problem replicating your example and wondered if
you are able to give me a hint. When I use the code from the
2007 Mar 14
1
How to transform matrices to ANOVA input datasets?
Hello, R experts,
I have a list called dataHP which has 30 elements (m1, m2, ..., m30).
Each element is a 7x6 matrix holding yield data from two factors
experimental design, with treatment in column, position in row. For
instance, the element 20 is:
dataHP[[20]]
col1 col2 col3 trt1 trt2 trt3
[1,] 22.0 20.3 29.7 63.3 78.5 76.4
[2,]
2012 Jan 27
1
Confused with Student's sleep data description
I am confused whether Student's sleep data "show the effect of two
soporific drugs" or Control against Treatment (one drug). The reason
is the next:
> require(stats)
> data(sleep)
> attach(sleep)
> extra[group==1]
numeric(0)
> group
[1] Ctl Ctl Ctl Ctl Ctl Ctl Ctl Ctl Ctl Ctl Trt Trt Trt Trt Trt Trt Trt Trt Trt
[20] Trt
Levels: Ctl Trt
> sleep$group
[1] 1 1 1 1 1
2008 Jun 04
1
"& not meaningful for factors"
I am trying to define groupings from levels of factor variables and this the warning message that R give
"& not meaningful for factors".
The nature of my task is this. I have a variable stage which has the levels (1B, 2A, 2B) - these are the AJCC TNM stages of cancer, and another variable diameter with factor levels ("=< 4", "4 - 6.5, > 6.5; limit values are
2013 Jul 24
1
Understanding modification in place
Hi all,
Take this simple script, which I'm trying to use to understand when
modification in-place occurs, and when a new object is created:
message("Global")
x <- 1:3
.Internal(inspect(x))
x[2] <- 1L
.Internal(inspect(x))
message("In function")
(function() {
x <- 1:3
.Internal(inspect(x))
x[2] <- 1L
.Internal(inspect(x))
})()
If I run it from the
2010 Dec 01
2
Lattice dotplots
Dear,
I have a dataset with 4 subjects (see ID in example), and 4 treatment (see
TRT in example) which are tested on 2 locations and in 3 blocs. By using
Lattice dotplot, I made a graph that shows the raw data per location and
per bloc. In that graph, I would like to have a reference line per bloc
that refers to the first treatment (T1). However, I can not find how to do
that.
I can make
2011 Apr 20
2
survexp with weights
Hello,
I probably have a syntax error in trying to generate an expected
survival curve from a weighted cox model, but I can't see it. I used
the help sample code to generate a weighted model, with the addition
of a "weights=albumin" argument (I only chose albumin because it had
no missing values, not because of any real relevance). Below are my
code with the resulting error
2013 Jan 24
1
Copy on assignment and .Internal(inspect())
Hi,
I would like to know if it's ok to use .Internal(inspect(x)) in order
to detect vector copying.
Take for example the following silly code:
f <- function() {
x = seq(10)
print(.Internal(inspect(x)))
for(i in seq(10)) {
x[i] <- x[i] + 1
print(.Internal(inspect(x)))
}
}
The output of f() was:
@bd7acf0 13 INTSXP g0c4 [NAM(1)] (len=10, tl=0) 1,2,3,4,5,...
[1] 1 2
2013 Feb 26
3
Merging value labels into indicator variable.
I have a vaiable named NAM having value : 1,2,3,4,5,6,7,8,9. I want to
make an indicator variable that will take value 1 if NAM=7 or NAM=8 or
NAM=9. How can I do that?
I usually do: Var001<- ifelse(NAM==7,1,0) for the simplest case.
[[alternative HTML version deleted]]
2017 Aug 09
2
Fill in empty spaces modified
Hi All?
I was looking at a posting from June-17. I managed to solve it. However,
when I changed the example in the posting, my solution will work only once
at a time which was mentioned by Jim Lemon on his response to the original
posting. This means that my solution will have to be repeated as many times
as the maximum number of spaces on each gap; something that may not work
well for large
2008 Mar 05
1
Question on "assign(paste.."
Hello,
I'm having trouble in using "assign(paste ..." command . I could create
several dataframes following trinomial distribution using it but it could
not be used to check their row means of the created dataframe.
For example, the following works:
probTrt=matrix(0,4,3);
probTrt;
#malf, death, normal
probTrt[1,]=c(0.064,0.119,0.817);#for Trt 1
probTrt[2,]=c(0.053,0.125,0.823);#for
2005 Feb 22
1
Re: R-help Digest, Vol 24, Issue 22
You need to give the model formula that gave your output.
There are two sources of variation (at least), within and
between locations; though it looks as though your analysis
may have tried to account for this (but if so, the terms are
not laid out in a way that makes for ready interpretation.
The design is such (two locations) that you do not have
much of a check that effects are consistent over
2012 May 29
2
use xyplot to plot mean and CI by groups
Dear R users,
I am trying to use xyplot to draw group mean and CI. The following is the
sample code. But I want:
1. Use different colors and symbols to draw individual points, CI and
the lines connect group means from different time points;
2. Add jitters to x axis to allow CIs not be overlapped
Could anyone modify the attached code to achieve this?
Thanks
library(lattice)
2011 Dec 11
2
multiple comparison of interaction of ANCOVA
Hi there,
The following data is obtained from a long-term experiments.
> mydata <- read.table(textConnection("
+ y year Trt
+ 9.37 1993 A
+ 8.21 1995 A
+ 8.11 1999 A
+ 7.22 2007 A
+ 7.81 2010 A
+ 10.85 1993 B
+ 12.83 1995 B
+ 13.21 1999 B
+ 13.70 2007 B
+ 15.15 2010 B
+ 5.69 1993 C
+ 5.76 1995 C
+ 6.39 1999
2005 Dec 09
1
lmer for 3-way random anova
I have been using lme from nlme to do a 3-way anova with all the effects treated as random. I was wondering if someone could direct me to an example of how to do this using lmer from lme4.
I have 3 main effects, tim, trt, ctr, and all the interaction effects tim*trt*ctr. The response variable is ge.
Here is my lme code:
dat <-
2011 May 03
3
ANOVA 1 too few degrees of freedom
I'm running an ANOVA on some data for respiration in a forest. I am having a
problem with my degrees of freedom. For one of my variables I get one fewer
degrees of freedom than I should.
I have 12 plots and I therefore expected 11 degrees of freedom, but instead
I got 10.
Any ideas?
I have some code and output below:
> class(Combined.Plot)
[1] "character"
>
2003 Mar 06
1
Problems with variable types.
Hi all,
I have problems in a dataframe variables types.
Look:
from a loop function:
for(...){
...
dados.fin <- rbind(dados.fin, c(L=j, A=j^2,
Nsp=nsps,
N=length(amosfin$SP),
AmT="am",NAm=nam,
AMST=amst))
dados.fin <- rbind(dados.fin, c(L=j, A=j^2,