Re: Variance of sample and whole dataset
- To: mathgroup at smc.vnet.net
- Subject: [mg51210] Re: Variance of sample and whole dataset
- From: "Steve Luttrell" <steve_usenet at _removemefirst_luttrell.org.uk>
- Date: Fri, 8 Oct 2004 02:55:07 -0400 (EDT)
- References: <ck340j$b1j$1@smc.vnet.net>
- Sender: owner-wri-mathgroup at wolfram.com
You can define a variance function thus: var[dataset_]:=(Apply[Plus,#^2]/Length[#]-(Apply[Plus,#]/Length[#])^2)&[dataset]; and use it as in this example: dataset={a,b,c}; var[dataset] giving (-(1/9))*(a + b + c)^2 + (1/3)*(a^2 + b^2 + c^2) Steve Luttrell "Uwe Ziegenhagen" <newsgroup at ziegenhagen.info> wrote in message news:ck340j$b1j$1 at smc.vnet.net... > Hello, > > with Variance[list] and StandardDeviation[list] I get the > variance/std.dev for samples. > > Is there any builtin command for the variance of whole dataset (division > by n, not by n-1)? > > Uwe > > > -- > > mail to newsgroup at ziegenhagen.info is read only from time to time. If > you need an urgent answer, google for me. >