Below. -- Bert
Bert Gunter Genentech Nonclinical Statistics -----Original Message----- From: r-help-boun...@r-project.org [mailto:r-help-boun...@r-project.org] On Behalf Of Liviu Andronic Sent: Tuesday, April 06, 2010 2:06 PM To: arindam fadikar Cc: r-help@r-project.org Subject: Re: [R] checking bivariate normality On Tue, Apr 6, 2010 at 12:48 PM, arindam fadikar <arindam.fadi...@gmail.com> wrote: > x <- iris$Sepal.Length[1:50]/iris$Sepal.Width[1:50] > y <- iris$Petal.Length[1:50]/iris$Petal.Width[1:50] > > I want to check whether (x,y) follows a bivariate normal distribution or > not, using density plot or scatter plot. Is it possible to plot a bivariate > density in R. I cant find any. > Perhaps there is something in mvnormtest? Liviu -- Doubt it, since it's _impossible_ to test whether "(x,y) follow a normal distribution." One might test whether the data are _consistent_ with bivariate normality (in the sense that evidence to the contrary is improbable in some sense), but that is a whole different kettle of fish. These is not mere semantic petulance; all too often there is fundamental misunderstanding about such issues. Precision of language is important. ______________________________________________ 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. ______________________________________________ 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.
