Hi, Please post in plain text and show the example using ?dput.
Assuming that you wanted a "data.frame" and not a "list" May be this helps: set.seed(428) dat1 <- data.frame(`block identifier`=rep(1:40,each=12),`block size`=12,`sequence within block`=rep(1:12,40), treatment=sample(paste("Group", LETTERS[1:2]), 12*40, replace=TRUE),age65= rep(sample(c("yes","no"), 40, replace=TRUE),each=12), surgery = rep(sample(c("yes","no"),40, replace=TRUE), each=12), smoke=rep(sample(c("Yes","No"), 40, replace=TRUE), each=12), check.names=FALSE,stringsAsFactors=FALSE) A.K. Dear R-listers, I am using R 3.1, I amtrying to generate 40 patients in each treatment group with 12 block, Equal number of treatment in each block ,using stratification Variable age65(yes, no),surgery(yes ,no) and smoke (yes, no) How can i creat like thislist in R. block identifier block size sequence within block treatment age65 surgery smoke 1 12 1 Group B yes yes Yes 1 12 2 Group A yes yes Yes 1 12 3 Group A yes yes Yes 1 12 4 Group B yes yes Yes 1 12 5 Group A yes yes Yes 1 12 6 Group B yes yes Yes 1 12 7 Group B yes yes Yes 1 12 8 Group A yes yes Yes 1 12 9 Group A yes yes Yes 1 12 10 Group B yes yes Yes 1 12 11 Group A yes yes Yes 1 12 12 Group B yes yes Yes 2 12 1 Group B yes yes no 2 12 2 Group A yes yes no 2 12 3 Group B yes yes no 2 12 4 Group B yes yes no 2 12 5 Group A yes yes no 2 12 6 Group A yes yes no 2 12 7 Group B yes yes no 2 12 8 Group A yes yes no 2 12 9 Group A yes yes no 2 12 10 Group B yes yes no 2 12 11 Group A yes yes no 2 12 12 Group B yes yes no I am very appreciate yourtime to answer my question Thanks Sug ______________________________________________ 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.