Displaying 20 results from an estimated 10000 matches similar to: "Fisher exact test?"
2013 Aug 28
1
Welcome to the "R-help" mailing list
Good Afternoon,
My name is Gabriel, I'm doing an analysis if there is increase or decrease in dependence on the mutated genes, using 3 or more genes using the fisher exact test.I performed with success an analysis for two genes using fisher.test( ). example of the 2x2 contigency table:
Gene A mutated | Gene A normalGene B mutated| 26
2010 May 12
1
read table for Fisher Exact
i have 2 groups i want to compare: group A and group B
each group contains let's say 20 patients
i want to perform a Fisher Exact test on genotype distribution
so, see if there is a sign diff in genotpe frequency/distribution (#AA, #AB,
#BB) between group A and B
not for 1, but for 1000 different genes
my question: how should i build my table so i can do:
test <-
2003 Apr 22
4
fisher exact vs. simulated chi-square
Dear All,
I have a problem understanding the difference between the outcome of a
fisher exact test and a chi-square test (with simulated p.value).
For some sample data (see below), fisher reports p=.02337. The normal
chi-square test complains about "approximation may be incorrect",
because there is a column with cells with very small values. I
therefore tried the chi-square with
2010 Sep 02
1
Linear models (lme4) - basic question
Hi,
Sorry for a basic questions on linear models.
I am trying to adjust raw data for both fixed and mixed effects. The data that I
output should account for these effects, so that I can use the adjusted data for
further analysis.
For example, if I have the blood sugar levels for 30 patients, and I know that
'weight' is a fixed effect and that 'height' is a random effect, what
2005 Jun 22
1
chisq test and fisher exact test
Hi,
I have a text mining project and currently I am working on feature
generation/selection part.
My plan is selecting a set of words or word combinations which have
better discriminant capability than other words in telling the group
id's (2 classes in this case) for a dataset which has 2,000,000
documents.
One approach is using "contrast-set association rule mining" while the
2011 Apr 28
5
fisher exact for > 2x2 table
I'm using fisher.exact on a 4x2 table and it seems to work.
Does anyone know exactly what is going on? I thought fisher.exact is only
for 2x2 tables.
Note: I can't use chi-squared because I have a couple of cells with 0 and <
5 observations.
--
View this message in context: http://r.789695.n4.nabble.com/fisher-exact-for-2x2-table-tp3481979p3481979.html
Sent from the R help
2013 Mar 12
1
Testing for significance of overlap in three sets - mantelhaen test?
Hi,
My apologies for the naive question!
I have three overlapping sets and I want to find the probability of finding
a larger/greater intersection for 'A intersect B intersect C' (in the
example below, I want to find the probability of finding more than 135
elements that are common in sets A, B & C). For a two set problem, I guess
I would do a Fisher or chi-square test. Here is what
2010 Jan 31
2
help on Venn's diagram
Hello!
I have this problem: I want to create a Venn's diagram with three lists of genes'names. The first is all the genome, the second a subset of it comprising all mitochondrial genes, and the third including all genes that correlate with a given gene.
This is what I do:
> library(gplots)
> A<-read.delim("F:/.../mito genes just names.txt")
>
2011 Feb 24
1
reshaping list into a contingency table
Hi all,
I have been struggling with this problem for a few days.
I have a data table like this:
gene rpkm1 diff1 rpkm2 diff2
gene1 23 50 13 120
gene2 111 220 827 1200
gene3 75 998 71 910
And I want to re-format it so that, for each gene, I have a 2x2 contingency
table, such as:
gene rpkm diff
gene1 23 50
gene1 13 120
gene2 111 220
gene2 827
2013 Feb 01
2
help on proportions
Hi:
Apologies for asking the following question. As?this may sound very basic and stupid for this forum?, I honestly do not know how to solve it and I do not have a teacher who can help me understand.
?
I have list of genes (200)?that are involved in a particular process and I call this as a?ProcSet.?? From an independent experiment I found that out of 10,000 genes, 1500 are significant and I
2003 Dec 03
1
multidimensional Fisher or Chi square test
Hello,
Is there a test for independence available based on a multidimensional
contingency table?
I've about 300 processes, and for each of them I get numbers for failures and
successes. I've two or more conditions under which I test these processes.
If I had just one process to test I could just perform a fisher or chisquare
test on a 2x2 contigency table, like this:
for one process:
2008 Sep 17
1
Exact test in nxm contingency table
Hello,
I am trying to find a permutation test that works on a general nxm table. The data set is small enough to have cells with too small counts to make chi2-approximation invalid. If the table was a 2x2 contingency table I would like to use a Fsher exact test (fisher.test) but that wont work in this general table.
Does there exist a general function for this test.
Best regards,
Magnus
2012 Dec 03
1
discrepancy in fisher exact test between R and wiki formula
Hi All. Sorry to bother you. I have a question about fisher exact test.
I counted the presence of gene mutation in two groups of samples. My data is as follows
Presence Absence
GroupA 4 6
GroupB 5 11
When using the formula of fisher exact test provided by wiki (http://en.wikipedia.org/wiki/Fisher%27s_exact_test), the p-value is 0.29.
But when
2011 Nov 17
1
Fisher Exact Test
This mean
First, I am no expert but I am analyzing some marketing data.
I have information on two versions of the same site, and I have data
on the number of times people filled out a form on each version
of the site.
Sample data:
Site 1 Site 2
Filled out form 10 35
Did not fill out form 50
2009 Jul 26
1
Is there an R implementation for the "Barnard's exact test" (a substitute for fisher.test) ?
Hello R help members. I came across today with an article on Barnard's exact
test (http://www.cytel.com/Papers/twobinomials.pdf), that is supposed to
give a more powerful fisher.test - Because it doesn't assume that we know
the row and column totals are in advance. Any pointers to such a function ?
Thanks, Tal
--
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My contact information:
2012 May 11
1
Fisher Test in R
Suppose we have the following data set:
Men Women
Dieting 10 30
Non-dieting 5 60
If I run the Fisher exact test in R then what does alternative = greater (or
less) imply? For example:
mat = matrix(c(10,5,30,60), 2,2)
fisher.test(mat,alternative ="greater")
I get the p-value = 0.01588 and odds ratio = 3.943534. Also, when I flip
the rows of
2010 Aug 12
3
Plotting one dot in a graph
I'd like to plot a point at the intersection of these two curves. Thanks
x <- seq(.2, .3, by = .01)
f <- function(x){
x*cos(x)-2*x**2+3*x-1
}
plot(x,f(x), type = "l")
abline(h = 0)
2005 Jun 03
3
p-value > 1 in fisher.test()
The following contingency table generates p-value > 1 from fisher.test()
ff = c(0,10,250,5000); dim(ff) = c(2,2); fhisher.test(ff)$p.value
Sean
[[alternative HTML version deleted]]
2005 Jun 03
3
p-value > 1 in fisher.test()
The following contingency table generates p-value > 1 from fisher.test()
ff = c(0,10,250,5000); dim(ff) = c(2,2); fhisher.test(ff)$p.value
Sean
[[alternative HTML version deleted]]
2008 Jul 10
3
What's the T-Value in fisher.test
I do not understand how to interpret this to find the T Value for the data.
Is there a way to figure this out, or another function that will provide
this for me using Fisher's Exact Test?
The outcome of my data is listed below.
data: DATA
p-value = 0.1698
alternative hypothesis: true odds ratio is not equal to 1
95 percent confidence interval:
0.6026805 79.8309210
sample estimates: