Re: [R] need help for t.test using by

any one 1Rnwb wrote: I am trying to do ttest for each plate which has equal number of disease and controls. by searching this forum I found one posting suggesting OP to use by(eo,PlateID, function(.sub) t.test(IL1Ra~Group,data=.sub)). when i modified this for my use I used to get the

Re: [R] need help for t.test using by

On Aug 19, 2009, at 9:00 AM, 1Rnwb wrote: any one I looked at your posting yesterday and could not figure out what your statistical question was, nor could I figure out how the t.test formula related to the column names in the data.frame. I saw no Group or IL1Ra variables in your

Re: [R] need help for t.test using by

Thanks for the reply, and sorry for not being clear, I have ELISA data for 50 plates, equal number of disease and control samples are located on each plates. I need to do the ttest between each proteins listed as prt1, prt2... prt50 on all the plates 1-50, however for some proteins i have data

[R] need help for t.test using by

I am trying to do ttest for each plate which has equal number of disease and controls. by searching this forum I found one posting suggesting OP to use by(eo,PlateID, function(.sub) t.test(IL1Ra~Group,data=.sub)). when i modified this for my use I used to get the pvalues for each plate, recently