# help

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## help

 Code a is working. But code b is given error like given below. How can I write code b? > a<-rmvnorm(750, mean=c(0, 0), +                        sigma=matrix(c(1, .3, .3, 1), ncol=2)) > head(a)             [,1]        [,2] [1,] -0.97622921 -0.87129405 [2,]  0.54763494  0.16080131 [3,] -1.16627647  0.31225125 [4,]  1.72541168  2.06513939 [5,]  0.05372489 -0.07525197 [6,] -0.85062230 -1.02188473 > b<-rmvnorm(round(500,0), mean=c(0,-1), +                        sigma=matrix(c(.3, 1,1,1,.3, 1, 1,1, .3), ncol=3)) Error in rmvnorm(round(500, 0), mean = c(0, -1), sigma = matrix(c(0.3,  :   mean and sigma have non-conforming size         [[alternative HTML version deleted]] ______________________________________________ [hidden email] mailing list -- To UNSUBSCRIBE and more, see https://stat.ethz.ch/mailman/listinfo/r-helpPLEASE do read the posting guide http://www.R-project.org/posting-guide.htmland provide commented, minimal, self-contained, reproducible code.
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## Re: help

 A 2 dim distribution must have a 2 x 2 covariance matrix. Your mean in b) specifies 2 dim, but your covariance matrix is 3x3. If you haven't just made a typo and you don't know what this means, then either consult statistics references or find someone to help you. Cheers, Bert Gunter "The trouble with having an open mind is that people keep coming along and sticking things into it." -- Opus (aka Berkeley Breathed in his "Bloom County" comic strip ) On Tue, Mar 16, 2021 at 10:55 AM hatice gürdil <[hidden email]> wrote: > Code a is working. But code b is given error like given below. How can I > write code b? > > > a<-rmvnorm(750, mean=c(0, 0), > +                        sigma=matrix(c(1, .3, .3, 1), ncol=2)) > > > head(a) >             [,1]        [,2] > [1,] -0.97622921 -0.87129405 > [2,]  0.54763494  0.16080131 > [3,] -1.16627647  0.31225125 > [4,]  1.72541168  2.06513939 > [5,]  0.05372489 -0.07525197 > [6,] -0.85062230 -1.02188473 > > > b<-rmvnorm(round(500,0), mean=c(0,-1), > +                        sigma=matrix(c(.3, 1,1,1,.3, 1, 1,1, .3), ncol=3)) > > Error in rmvnorm(round(500, 0), mean = c(0, -1), sigma = matrix(c(0.3,  : >   mean and sigma have non-conforming size > >         [[alternative HTML version deleted]] > > ______________________________________________ > [hidden email] mailing list -- To UNSUBSCRIBE and more, see > 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. >         [[alternative HTML version deleted]] ______________________________________________ [hidden email] mailing list -- To UNSUBSCRIBE and more, see https://stat.ethz.ch/mailman/listinfo/r-helpPLEASE do read the posting guide http://www.R-project.org/posting-guide.htmland provide commented, minimal, self-contained, reproducible code.