To me, correlation measures the linear association between paired observations. Since the pairing is essential, how could the datasets not be the same length? --Naomi At 10:12 AM 1/31/2007, Damion Colin Nero wrote: >I am using the rcor.test function available in the ltm package and >wanted to know if there was a way to use this function to compute the >correlation of two datasets that are not of equal length (similar to the >base cor function). I was thinking an apply function like by might work >but so far I have had no luck getting it to work.I was wondering if >anyone could give me some general advice on this. > >Damion Nero >Plant Molecular Biology Lab >Department of Biology >New York University > >_______________________________________________ >Bioconductor mailing list >Bioconductor at stat.math.ethz.ch >https://stat.ethz.ch/mailman/listinfo/bioconductor >Search the archives: >http://news.gmane.org/gmane.science.biology.informatics.conductor Naomi S. Altman 814-865-3791 (voice) Associate Professor Dept. of Statistics 814-863-7114 (fax) Penn State University 814-865-1348 (Statistics) University Park, PA 16802-2111

What I am looking for is to pair one observation with all others as computing all possible pairwise correlations is computationally unfeasible using R with very large datasets Damion Nero Plant Molecular Biology Lab Department of Biology New York University ----- Original Message ----- From: Naomi Altman <naomi@stat.psu.edu> Date: Friday, February 2, 2007 3:31 pm Subject: Re: [BioC] rcor.test > To me, correlation measures the linear association between paired > observations. Since the pairing is essential, how could the > datasets > not be the same length? > > --Naomi > > At 10:12 AM 1/31/2007, Damion Colin Nero wrote: > >I am using the rcor.test function available in the ltm package and > >wanted to know if there was a way to use this function to compute the > >correlation of two datasets that are not of equal length (similar > to the > >base cor function). I was thinking an apply function like by > might work > >but so far I have had no luck getting it to work.I was wondering if > >anyone could give me some general advice on this. > > > >Damion Nero > >Plant Molecular Biology Lab > >Department of Biology > >New York University > > > >_______________________________________________ > >Bioconductor mailing list > >Bioconductor at stat.math.ethz.ch > >https://stat.ethz.ch/mailman/listinfo/bioconductor > >Search the archives: > >http://news.gmane.org/gmane.science.biology.informatics.conductor > > Naomi S. Altman 814-865-3791 (voice) > Associate Professor > Dept. of Statistics 814-863-7114 (fax) > Penn State University 814-865-1348 > (Statistics)University Park, PA 16802-2111 > >

I still don't understand what you are trying to do. Do you mean that you have k variables of length n in 1 group, and m variables also of length k in another and you want to compute all the correlations between variables in the 2 groups? --Naomi At 05:27 PM 2/2/2007, Damion Colin Nero wrote: >What I am looking for is to pair one observation with all others as >computing all possible pairwise correlations is computationally >unfeasible using R with very large datasets > >Damion Nero >Plant Molecular Biology Lab >Department of Biology >New York University > > >----- Original Message ----- >From: Naomi Altman <naomi at="" stat.psu.edu=""> >Date: Friday, February 2, 2007 3:31 pm >Subject: Re: [BioC] rcor.test > > > To me, correlation measures the linear association between paired > > observations. Since the pairing is essential, how could the > > datasets > > not be the same length? > > > > --Naomi > > > > At 10:12 AM 1/31/2007, Damion Colin Nero wrote: > > >I am using the rcor.test function available in the ltm package and > > >wanted to know if there was a way to use this function to compute the > > >correlation of two datasets that are not of equal length (similar > > to the > > >base cor function). I was thinking an apply function like by > > might work > > >but so far I have had no luck getting it to work.I was wondering if > > >anyone could give me some general advice on this. > > > > > >Damion Nero > > >Plant Molecular Biology Lab > > >Department of Biology > > >New York University > > > > > >_______________________________________________ > > >Bioconductor mailing list > > >Bioconductor at stat.math.ethz.ch > > >https://stat.ethz.ch/mailman/listinfo/bioconductor > > >Search the archives: > > >http://news.gmane.org/gmane.science.biology.informatics.conductor > > > > Naomi S. Altman 814-865-3791 (voice) > > Associate Professor > > Dept. of Statistics 814-863-7114 (fax) > > Penn State University 814-865-1348 > > (Statistics)University Park, PA 16802-2111 > > > > Naomi S. Altman 814-865-3791 (voice) Associate Professor Dept. of Statistics 814-863-7114 (fax) Penn State University 814-865-1348 (Statistics) University Park, PA 16802-2111