Manual estimation of sums of squares ancdoug=read.table('ancdoug.txt',header=T) attach(ancdoug) #Sums and sums of squares for diet a1 sum(pre[diet=="a1"]);sum(pre[diet=="a1"]^2) sum(post[diet=="a1"]);sum(post[diet=="a1"]^2) sum(pre[diet=="a1"]*post[diet=="a1"]) #Sums and sums of squares for diet a2 sum(pre[diet=="a2"]);sum(pre[diet=="a2"]^2) sum(post[diet=="a2"]);sum(post[diet=="a2"]^2) sum(pre[diet=="a2"]*post[diet=="a2"]) #Sums and sums of squares for diet a3 sum(pre[diet=="a3"]);sum(pre[diet=="a3"]^2) sum(post[diet=="a3"]);sum(post[diet=="a3"]^2) sum(pre[diet=="a3"]*post[diet=="a3"]) sum(pre);sum(pre^2) sum(post);sum(post^2) sum(pre*post) detach(ancdoug)