Re: [R] t-test for standard deviations

From: Ted Harding <Ted.Harding_at_nessie.mcc.ac.uk>
Date: Fri 13 Jan 2006 - 05:52:33 EST


On 12-Jan-06 mirko sanpietrucci wrote:
> Dear R-users,
> I am new to the list and I would like to submit (probably!!!!)
> a stupid question:
>
> I found in a paper a reference to a t-test for the evaluationg the
> difference between the standard deviations of 2 samples.
> This test is performed in the paper but the methodology is not
> explained and any reference is reported.
>
> Does anyone know where I can find references to this test and if it is
> implemented in R?
>
> Thenks in advance for your help,
>
> Mirko

If the paper says that a

  1. "t-test"

was used for evaluating the difference between the

2) "standard deviations"

of 2 samples

then I suspect that one or the other of these is a misprint.

To compare standard deviations (more precisely, variances) you could use a (1)F-test.

Or you would use a t-test to evaluate the difference between the (2)means of 2 samples.

If it is really obscure what was done, perhaps an appropriate quotation from the paper would help to ascertain the problem.

Best wishes,
Ted.



E-Mail: (Ted Harding) <Ted.Harding@nessie.mcc.ac.uk> Fax-to-email: +44 (0)870 094 0861
Date: 12-Jan-06                                       Time: 18:52:31
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