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Re: Re: Normality test

• To: mathgroup at smc.vnet.net
• Subject: [mg107112] Re: [mg107100] Re: Normality test
• From: michael partensky <partensky at gmail.com>
• Date: Wed, 3 Feb 2010 06:09:16 -0500 (EST)
• References: <hk8nns$8jv$1@smc.vnet.net> <201002021154.GAA15812@smc.vnet.net>

Thanks, Ray.
Michael Partenskii

On Tue, Feb 2, 2010 at 6:54 AM, Ray Koopman <koopman at sfu.ca> wrote:

> On Feb 2, 12:28 am, michael partensky <parten... at gmail.com> wrote:
> > Hi.
> > I wonder if anybody knows a function similar to qqnorm(data) from *R*,
> > producing a normal scores plot, or some related tools in M. for testing
> > normality of data?
> >
> > Thanks
> > Michael Partenskii
>
> qqnorm[y_] := Block[
>  {n = Length@y, m = Mean@y, s = StandardDeviation@y, x},
>  x = InverseErf[Range[1-n,n-1,2]/n]*Sqrt[2.];
>  ListPlot[Transpose@{x,Sort@y},
>  PlotRange->All, Frame->True, Axes->None, AspectRatio->1,
>  Prolog->Line[{{x[[1]],x[[1]]*s+m},{x[[-1]],x[[-1]]*s+m}}],
>  FrameLabel->{"Theoretical Standard Normal Quantiles",
>               "Observed Quantiles"}]]
>
>

• References:
  • Re: Normality test
    • From: Ray Koopman <koopman@sfu.ca>