Re: st: somersd resampling question

[Roger Newson <r.newson@imperial.ac.uk>]

Resampling is valid with -somersd-, as long as the units resampled are 
clusters rather than non-independent observations within clusters. In 
your case, if you start with frequency counts and want to use a 
resampling method, then you will presumably have to expand the dataset 
(using -expgen-, -reshape- or some similar command) to get the units to 
be resampled.

I hope this helps.

Best wishes

Roger


Roger B Newson BSc MSc DPhil
Lecturer in Medical Statistics
Respiratory Epidemiology and Public Health Group
National Heart and Lung Institute
Imperial College London
Royal Brompton Campus
Room 33, Emmanuel Kaye Building
1B Manresa Road
London SW3 6LR
UNITED KINGDOM
Tel: +44 (0)20 7352 8121 ext 3381
Fax: +44 (0)20 7351 8322
Email: r.newson@imperial.ac.uk
Web page: http://www.imperial.ac.uk/nhli/r.newson/
Departmental Web page:
http://www1.imperial.ac.uk/medicine/about/divisions/nhli/respiration/popgenetics/reph/

Opinions expressed are those of the author, not of the institution.

On 29/10/2010 17:04, Feiveson, Alan H. (JSC-SK311) wrote:
> Hi - I want to use Kendall's Tau-a to characterize similarity between two multinomial samples. My question is whether the resampling in -somersd- to get standard errors is valid when comparing two multinomial samples, since technically the "obervations" (i.e. frequency counts) are not mutually independent. Anyone have an opinion on this?
>
> Thanks
>
> Al Feiveson
>
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