Displaying 20 results from an estimated 1000 matches similar to: "Proportion test in three-chices experiment"
2009 Apr 04
1
Problem with sample()
Hi,
I'm having a problem using sample() within a function.
Basically I get an error reading:
Error in sample(v, 1, prob = h) : non-positive probability
Can anyone advise me as to the possible origin of this error?
Here is my code
#Discretised Gillespie algorithm function (From SMfSB, D.J. Wilkinson)
gillespied=function (N, T=100, dt=1, ...)
{
tt=0
n=T%/%dt
x=N$M
2007 Apr 11
1
Programming Problem (for loop, random # control, 3 dimentional graph)
Dear List,
This is just a programming problem which i cannot seem
to figure out. I am trying to get a set of power from
a test (say, kolmogorov smirnov) out of a distribution
(say, G-K distribution) as follows. I am trying to
reduce to pain of writing the whole set of data points
(p# below) using "for" loop. However, I seem to have
some problem in it as the output "M" does not
2009 Nov 02
2
a prolem with constrOptim
Hi,
I apologize for the long message but the problem I encountered can't be stated in a few lines.
I am having some problems with the function constrOptim. My goal is to maximize the likelihood of product of K multinomials, each with four catagories under linear constraints on the parameter values. I have found that the function does not work for many data configurations.
#The likelihood
2008 Feb 11
3
Difference between P.Value and adj.P.Value
Hallo,
> fit12<-lmFit(qrg[,1:2])
> t12<-toptable(fit12,adjust="fdr",number=25,genelist=qrg$genes[,1])
> t12
ID logFC t P.Value adj.P.Val B
522 PLAU_OP -6.836144 -8.420414 5.589416e-05 0.01212520 2.054965
1555 CD44_WIZ -6.569622 -8.227938 6.510169e-05 0.01212520 1.944046
Can anyone tell me what the difference is between P.Value
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
2008 Jul 09
1
Help with installing add-on packages
Dear R users.
Recently I wanted to update my R distribution to the current one (R-2.7.1). I am running a Fedora core 8 distirbution. The installation went fine, but when I tried to add some additional packages the majority made an exit with an error. Only a few least demanding (e.g. RColorBrewer) managed to get through the installation process.
What happened between the versions 2.6.x and 2.7.x
2023 Aug 31
1
simulating future observations from heteroscedastic fits
Hello, All:
I want to simulate future observations from fits to heteroscedastic
data. A simple example is as follows:
(DF3_2 <- data.frame(y=c(1:3, 10*(1:3)),
gp=factor(rep(1:2, e=3))))
# I want to fit 4 models
# and simulate future observations from all 4:
fit11 <- lm(y~1, DF3_2)
fit21 <- lm(y~gp, DF3_2)
library(nlme)
(fit12 <- lme(y~1, data=DF3_2,
2008 Sep 18
2
Problem installing packages in newer versions of R
Dear all,
I was wandering what could be wrong with my system (regularly updated Fedora core 8) so that installing packages does not succeed with almost every package. I follow the procedure specified in the help file R-admin section 6.3. This is not a feature new to the current version but happened (to me) in the previous version as well. Additionally R-help html pages try to follow wrong links
2008 Jan 24
3
store variable as tab-del. txt-file
Hallo,
how can I store a variable as a tab-delimited txt-file? I crated a
variable with the following commands:
> fit12<-lmFit(qrg[,1:2])
> t12<-toptable(fit12,adjust="fdr",number=25,genelist=qrg$genes[,1])
> t12
ID logFC t P.Value adj.P.Val B
522 PLAU_OP -6.836144 -8.420414 5.589416e-05 0.01212520 2.054965
1555 CD44_WIZ -6.569622
2011 Jan 05
1
Comparing fitting models
Dear all,
I have 3 models (from simple to complex) and I want to compare them in order to
see if they fit equally well or not.
From the R prompt I am not able to see where I can get this information.
Let´s do an example:
fit1<- lm(response ~ stimulus + condition + stimulus:condition, data=scrd)
#EQUIVALE A lm(response ~ stimulus*condition, data=scrd)
fit2<- lm(response ~ stimulus +
2011 Jan 05
2
Problem with 2-ways ANOVA interactions
Dear All,
I have a problem in understanding how the interactions of 2 ways ANOVA work,
because I get conflicting results
from a t-test and an anova. For most of you my problem is very simple I am sure.
I need an help with an example, looking at one table I am analyzing. The table
is in attachment
and can be imported in R by means of this command:
scrd<-
2013 Feb 25
1
creating variable that codes for the match/mismatch between two other variables
Dear all,
I have got two vectors coding for a stimulus presented in the current trial (mydat$Stimulus) and a prediction in the same trial (mydat$Prediciton), respectively.
By applying an if-conditional I want to create a new vector that indicates if there is a match between both vectors in the same trial. That is, if the prediction equals the stimulus.
When I pick out some trials randomly, I get
2005 Dec 01
1
LME & data with complicated random & correlational structures
Dear List,
This is my first post, and I'm a relatively new R user trying to work out a
mixed effects model using lme() with random effects, and a correlation
structure, and have looked over the archives, & R help on lme, corClasses, &
etc extensively for clues. My programming experience is minimal (1 semester
of C). My mentor, who has much more programming experience, but a comparable
2010 Jun 13
1
Pairwise cross correlation from data set
Dear list,
Following up on an earlier post, I would like to reorder a dataset and
compute pairwise correlations. But I'm having some real problems
getting this done.
My data looks something like:
Participant Stimulus Measurement
p1 s`1 5
p1 s`2 6.1
p1 s`3 7
p2 s`1 4.8
p2
2006 May 11
2
greco-latin square
Hi,
I am analyzing a repeated-measures Greco-Latin Square with the aov command.
I am using aov to calculate the MSs and then picking by hand the appropriate
neumerator and denominator terms for the F tests.
The data are the following:
responseFinger
mapping.code Subject.n index middle ring
little
----------------------------------------------------------------------------
1 1
2007 Aug 02
1
ggplot2 qplot and add
Hi there,
I have some simple frequencies I want to plot into one graph. I had it
working, and now I can't figure out whats going wrong. All the data is
stored in a dataframe, and i finally managed to order the factor correctly!
Each column is a variable and contains integers for the same set of values
in the column that contains the headers for each row (graphLabels).
So, I get the data
2011 Jan 08
1
Anova with repeated measures for unbalanced design
Dear all,
I need an help because I am really not able to find over internet a good example
in R to analyze an unbalanced table with Anova with repeated measures.
For unbalanced table I mean that the questions are not answered all by the same
number of subjects.
For a balanced case I would use the command
aov1 = aov(response ~ stimulus*condition + Error(subject/(stimulus*condition)),
data=scrd)
2006 Jan 22
1
NAs in optim
Hi,
I am trying to maximize a utility function using optim. I have a problem
with optim, since some of the values in the caw, mom, me and btm matrixes in
the code bellow are missing. Is there a handy way just to skip the missing
values in the loop?
g <- 5
retp <- NULL
object <- function (x)
{
b1 <- x[1]
b2 <- x[2]
b3 <- x[3]
for(i in 1:nrow(ret)){
for(j
2011 Jan 07
2
anova vs aov commands for anova with repeated measures
Dear all,
I need to understand a thing in the beheaviour of the two functions aov and
anova in the following case
involving an analysis of ANOVA with repeated measures:
If I use the folowing command I don´t get any problem:
>aov1 = aov(response ~ stimulus*condition + Error(subject/(stimulus*condition)),
>data=scrd)
> summary(aov1)
Instead if I try to fit the same model for the
2011 Jan 09
2
Post hoc analysis for ANOVA with repeated measures
Dear all,
how can I perform a post hoc analysis for ANOVA with repeated measures (in
presence of a balanced design)?
I am not able to find a good example over internet in R...is there among you
someone so kind to give
me an hint with a R example please?
For example, the aov result of my analysis says that there is a statistical
difference between stimuli (there are 7 different stimuli).
...I