On Dec 1, 2012, at 01:00 , David Winsemius wrote: > > On Nov 30, 2012, at 1:05 PM, jaybell wrote: > >> sorry, I repost the question again > > Why? This was already answered. > >> >> a=c(0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9) >> b=c(0.9, 0.8, 0.7, 0.6, 0.5, 0.4, 0.3, 0.2, 0.1) >> cor(a,b)= -1 >> >> pa=qbinom(a, 1, 0.5) >> pb=qbinom(b, 1, 0.5) >> cor(pa,pb)=-0.8 >> >> but when >> pa=qbinom(a,10,0.5) >> pb=qbinom(b,10,0.5) >> >> cor(pa,pb) becomes -1 again > > What part of "plot the values" was difficult to understand?
(Actually, "list the values" might be more informative in this case: > pa [1] 0 0 0 0 0 1 1 1 1 > pb [1] 1 1 1 1 0 0 0 0 0 Notice that pb != 1-pa when size=1.) -- Peter Dalgaard, Professor, Center for Statistics, Copenhagen Business School Solbjerg Plads 3, 2000 Frederiksberg, Denmark Phone: (+45)38153501 Email: pd....@cbs.dk Priv: pda...@gmail.com ______________________________________________ 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.