I tried your sample code, and a few other variations, and got 0 for all of them, running R 1.8.1 on a Windows machine
Peter Peter L. Flom, PhD Assistant Director, Statistics and Data Analysis Core Center for Drug Use and HIV Research National Development and Research Institutes 71 W. 23rd St www.peterflom.com New York, NY 10010 (212) 845-4485 (voice) (917) 438-0894 (fax) >>> Andreas Pauling <[EMAIL PROTECTED]> 3/29/2004 9:01:40 AM >>> Dear R people I came across a strange thing: sd(rep(0.01, 15)) #0 sd(rep(0.001, 15)) #4.489023e-19 sd(rep(0.00001, 15)) #0 sd(rep(0.00000001,15)) #1.712427e-24 sd(rep(0.01, 13)) #1.805557e-18 sd(rep(0.001, 13)) #4.513894e-19 sd(rep(0.00001, 13)) #0 sd(rep(0.00000001,13)) #0 sd(rep(5.01, 15)) #0 sd(rep(5.001, 15)) #4.489023e-19 sd(rep(5.00001, 15)) #1.838704e-15 sd(rep(5.00000001,15)) #9.19352e-16 sd(rep(5.01, 13)) #9.244454e-16 sd(rep(5.001, 13)) #9.244454e-16 sd(rep(5.00001, 13)) #1.848891e-15 sd(rep(5.00000001,13)) #0 Why gives sd sometimes zero and sometimes values close to zero and why does it depend on the value and on how many times it is repeated? Shouldn't it give always zero? Is there a way to control this? I use R Version 1.8.1 under UNIX. Thanks for any suggestions!! Andreas ______________________________________________ [EMAIL PROTECTED] mailing list https://www.stat.math.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html ______________________________________________ [EMAIL PROTECTED] mailing list https://www.stat.math.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html