You might like to use the -somersd- package, downloadable from SSC using
the -ssc- command. The -somersd- package produces confidence intervals for
rank statistics, which are more informative than P-values alone. In the case
of the Wilcoxon test, you can either use the program -somersd- to calculate
confidence intervals for Somers' D, or you can use the program -cendif-
(part of the -somersd- package) to calculate confidence limits for
Hodges-Lehmann median differences or ratios. Both -somersd- and -cendif-
come with .pdf manuals, distributed as part of the -somersd- package.
I hope this helps.
Roger
--
Roger Newson
Lecturer in Medical Statistics
Department of Public Health Sciences
Division of Asthma, Allergy and Lung Biology
King's College London
5th Floor, Capital House
42 Weston Street
London SE1 3QD
United Kingdom
Tel: 020 7848 6648 International +44 20 7848 6648
Fax: 020 7848 6620 International +44 20 7848 6620
or 020 7848 6605 International +44 20 7848 6605
Email: [email protected]
Website: http://phs.kcl.ac.uk/rogernewson/
Opinions expressed are those of the author, not the institution.
Stefania wrote:
We ran an experiment with 24 subjects for each treatment. They had to
choose how to invest their initial endowment. They had the opportunity to
invest this sum both in a public good and in a private good. We ran
different treatments where the game was repeated for 8 periods. If I want
to compare the average contribution to the public good in two different
treatments, is the Mann-Whitney test suitable (we have different players
in each treatment)? Should the Jonckheere test provide a better
performance? Thank you. Stefania
*
* For searches and help try:
* http://www.stata.com/support/faqs/res/findit.html
* http://www.stata.com/support/statalist/faq
* http://www.ats.ucla.edu/stat/stata/
