Easy. See below. Bert Gunter Genentech Nonclinical Biostatistics -----Original Message----- From: r-help-boun...@r-project.org [mailto:r-help-boun...@r-project.org] On Behalf Of Tom La Bone Sent: Monday, March 29, 2010 6:56 AM To: r-help@r-project.org Subject: Re: [R] Ellipse that Contains 95% of the Observed Data
Concisely, here is what I am trying to do: #I take a random sample of 300 measurements. After I have the measurements #I post stratify them to 80 type A measurements and 220 type B measurements. #These measurements tend to be lognormally distributed so I fit them to #determine the geometric mean and geometric standard deviation of each stratum. #The question is: are the geometric mean and geometric standard deviation of #the type A measurements the same as the geometric mean and geometric #standard deviation of the type B measurements? -- No. (So you probably need to 1. Ask a more statistically meaningful question. 2. Get a MUCH larger sample (you're talking about bivariate sd's here!!) ) -- Bert ______________________________________________ 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.
