Displaying 20 results from an estimated 1000 matches similar to: "Questions of Significance Analysis of Microarrays(SAM){siggenes}"
2011 Feb 09
1
samr - extract genes from siggenes.table
Hi BioC user,
I have a problem extracting the gene set I would like to work with.
Here is I work with my data:
normData <- read.delim("normalizedData.txt",sep ="\t")
######### two class unpaired comparison
# y must take values 1,2
classes <- c(-1,-2,1,2)
#prepere the data for the samr analysis
data.x <-as.matrix(normData[,8:11])
d=list(x=data.x,y=classes,
2007 Jan 23
3
the value of Delta
Dear all,
I am running R 2.4.1.
> library(siggenes);
> library(multtest);
> cl<-rep(c(0,1),c(3,3));
> sub<-exprs(AffyExpData[,c(1:3,7:9)]);
> gn<-geneNames(AffyRAwData);
> sam.out<-sam(sub,cl,rand=123,gene.names=gn);
We're doing 20 complete permutations
> sam.out
SAM Analysis for the Two-Class Unpaired Case Assuming Unequal Variances
Delta p0
2006 Nov 18
1
Why SAM has totally diffent results in R2.1.1 and R2.4.0
Hi,
I am using SAM (from siggenes_1.2.11 package) method to select genes from
a microarray data set. After installing the latest R2.4.0 on my computer, to
my surprise the results are totally different from that calculated using
R2.1.1. Even the example code doesn't work the same way under these two
versions of R. Does anybody know what is going on? Thanks for any
suggestions.
2004 Dec 20
1
[BioC] limma, FDR, and p.adjust
You asked the same question on the Bioconductor mailing list back in August. At that time, you
suggested yourself a solution for how the adjusted p-values should be interpreted. I answered
your query and told you that your interpretation was correct. So I'm not sure what more can be
said, except that you should read the article Wright (1992), which is cited in the help entry for
p.adjust(),
2012 Mar 30
1
Help with the lumi R package
Hi all,
My name is Amy, I am a masters student in Bioinformatics at North Carolina
State University. I am working on a project and I am trying to use the lumi
R package for microarray data analysis. I have shown the sample code here
and have questions about modifying the sample code for my own data.
lumi package in R, example.lumi, the sample data has 8000 features and 4
samples
I have
2008 May 06
1
Significance analysis of Microarrays (SAM)
Dear list,
I am trying to perform a significance analysis of a microarray experiment
with survival data using the {samr} package. I have a matrix containing my
data which has 17816 rows corresponding to genes, and 286 columns
corresponding to samples. The name of this matrix is data.matrix2. Some of
the first values of this matrix are:
data.matrix2[1:3,1:5]
GSM36777 GSM36778 GSM36779
2007 Feb 28
2
topTable function from LIMMA
Dear R-Help,
I am using the function "topTable" from the LIMMA package. To estimate
adjusted P-values there are several options (adjust="fdr" , adjust="BH")
as shown below:
topTable(fit, number = 10, adjust = "BH", fit$Name)
I guess any of these options (fdr, BH, etc.) is using a default of
FDR=0.05 which is quite conservative (i.e., very
2010 Sep 20
1
Please help with this error - new to
I am getting the following error in my script. I am very very new to R and
have obtained this script from another person.
#read file in (dummy data)
starburst.plot<-function(affy.fold, affy.FDR)(ifelse( ((affy.fold) >=0),
-1*log10(affy.FDR), 1*log10(affy.FDR)))
starburst.plot<-function(meth.fold, meth.FDR)(ifelse( ((meth.fold) >=0),
-1*log10(meth.FDR), 1*log10(affy.FDR)))
At my next
2004 Nov 18
3
Redirect standard input and output of R
Dear R-people!
I??m trying to write a C program that write to the standard input of R
and read the standard output.
I can perfectly read the R output, but I??m not able of writing anything
to R.
This program really works with the 'cat?? UNIX command, but it does not
work with R. What I??m doing wrong??? It is possible to do it???
I want to start R once and use it thousands of times...
2004 Nov 18
3
Redirect standard input and output of R
Dear R-people!
I??m trying to write a C program that write to the standard input of R
and read the standard output.
I can perfectly read the R output, but I??m not able of writing anything
to R.
This program really works with the 'cat?? UNIX command, but it does not
work with R. What I??m doing wrong??? It is possible to do it???
I want to start R once and use it thousands of times...
2004 Dec 20
2
problems with limma
I try to send this message To Gordon Smyth at smyth at vehi,edu.au but it bounced
back, so here it is to r-help
I am trying to use limma, just downloaded it from CRAN. I use R 2.0.1 on Win XP
see the following:
> library(RODBC)
> chan1 <- odbcConnectExcel("D:/Data/mgc/Chips/Chips4.xls")
> dd <- sqlFetch(chan1,"Raw") # all data 12000
> #
> nzw <-
2008 Jul 10
2
false discovery rate !
Dear All,
It is not a typical R question (though I use R for this) but I thought someone will help me. For the list of P values, I have calculated FDR using p.adjust() in R (bioconductor). But my FDR values are same for all the P values. When do we get same FDR values? Does the smallest P values should less than 1/N? (where N is the number of P values)
Thanks in advance.
Kind regards,
Ezhil
2004 Oct 19
2
Questions of t.test {stats}
We are currently using the t-test in Package stats,
t.test(x, y = NULL, alternative = c("two.sided", "less", "greater"),
mu = 0, paired = FALSE, var.equal = FALSE,
conf.level = 0.95, ...)
but have some troubles :
1. why does the t-test take so a long time to perform a single test on a row
of a data.frame ? Is there any alternative function to perform
2003 Nov 03
1
FDR in p.adjust
Hello,
I've a question about the fdr method in p.adjust: What is the threshold of
the FDR, and is it possible to change this threshold?
As I understand the FDR (please correct) it adjusts the p-values so that for
less than N% (say the cutoff is 25%) of the alternative hypothesis the Null
is in fact true.
thanks a lot for help,
+regards,
Arne
2006 Aug 31
1
problem with postscript output of R-devel on Windows
I have developed a problem with the postscript output of plot on Windows. My code still works properly with R 2.3 but, with R 2.4, the white text on red background does not show up. It does, however, show up when output is sent to the screen. Below is my code and sessionInfo.
R version 2.4.0 Under development (unstable) (2006-08-29 r39012)
i386-pc-mingw32
locale:
LC_COLLATE=English_United
2008 Jun 27
0
SAM FDR
Hello all,
I am doing SAM and the median of positive genes in the permutated sets is =
false positives, and the "parent set" gives true positives.
FDR = FP/TP * 100.
My FDR comes to greater than 100.
Is that possible?
Please help!
Thanks,
-D.
[[alternative HTML version deleted]]
2005 Jul 14
2
Partek has Dunn-Sidak Multiple Test Correction. Is this the same/similar to any of R's p.adjust.methods?
The Partek package (www.partek.com) allows only two selections for Multiple
Test Correction: Bonferroni and Dunn-Sidak. Can anyone suggest why Partek
implemented Dunn-Sidak and not the other methods that R has? Is there any
particular advantage to the Dunn-Sidak method?
R knows about these methods (in R 2.1.1):
> p.adjust.methods
[1] "holm" "hochberg" "hommel"
2010 Oct 07
1
FDR
Dear R users,
I am wondering about the following results:
> p.adjust(c(0.05,0.05,0.05),"fdr")
[1] 0.05 0.05 0.05
> p.adjust(c(0.05,0.04,0.03),"fdr")
[1] 0.05 0.05 0.05
Why does p.adjust(..., "fdr") not adjust p-values, if they are constant?
Does somebody have an explanation or can point to a reference?
Thanks in advance,
Will
2017 Aug 16
0
Is transport=rdma tested with "stripe"?
> Note that "stripe" is not tested much and practically unmaintained.
Ah, this was what I suspected. Understood. I'll be happy with "shard".
Having said that, "stripe" works fine with transport=tcp. The failure reproduces with just 2 RDMA servers (with InfiniBand), one of those acts also as a client.
I looked into logs. I paste lengthy logs below with
2017 Aug 18
1
Is transport=rdma tested with "stripe"?
On Wed, Aug 16, 2017 at 4:44 PM, Hatazaki, Takao <takao.hatazaki at hpe.com> wrote:
>> Note that "stripe" is not tested much and practically unmaintained.
>
> Ah, this was what I suspected. Understood. I'll be happy with "shard".
>
> Having said that, "stripe" works fine with transport=tcp. The failure reproduces with just 2 RDMA servers