HI, A typo in my solution: row.names(res2)<-unlist(unique(lapply(strsplit(colnames(dat2),"_"),`[`,1)))
^^^^ A.K. ----- Original Message ----- From: "Nundy, Shantanu" <snu...@chicagobooth.edu> To: "r-help@r-project.org" <r-help@r-project.org> Cc: Sent: Wednesday, October 10, 2012 7:09 PM Subject: Re: [R] multiple t-tests across similar variable names Hi everyone- I have a dataset with multiple "pre" and "post" variables I want to compare. The variables are named "apple_pre" or "pre_banana" with the corresponding post variables named "apple_post" or "post_banana". The variables are in no particular order. apple_pre orange_pre orange_post pre_banana apple_post post_banana person_1 person_2 person_3 ... person_x How do I: 1. Run a series of paired t-tests for the apple_pre variables and pre_banana variables? Would be great to do something like ttest(*.*pre*.*,*.*post*.*). 2. Print the results from these t-tests in a table with col 1=mean difference, col 2= 95% conf interval, col 3=p-value. Thank you kindly, -Shantanu Shantanu Nundy, M.D. University of Chicago [[alternative HTML version deleted]] ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code. ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
