Thanks to Kit Baum, there is now a new version of the -parmest- package
downloadable from SSC. The -parmest- package saves the results of an
estimation command as a Stata data set with 1 observation per parameter, or
1 observation per parameter per by-group, and data on estimates, confidence
limits, P-values, and other results if requested. Type -ssc describe
parmest- in Web-aware Stata to find out more.
The new version fixes a bug, which caused -parmest- to fail if used with
the survey estimation commands -svymean-, -svyratio- and -svytotal- when
these commands were specified with the -available- option instead of the
-complete- option. -parmest- now works with these survey estimation
commands when the -available- option is specified. In these circumstances,
-parmest- now calculates confidence limits and P-values using estimates in
e(est) and variances extracted from e(V_db), and the default degrees of
freedom formula used is e(N_psu)-e(N_strata), as specified in -[R] svymean-
under the sub-section "Confidence intervals". All other Stata estimation
commands store the estimates in e(b), the variances in e(V) and the degrees
of freedom in e(df_r), and so do -svymean-, -svyratio- and -svytotal- when
the -complete- option is specified instead of the -available- option. When
working with these commands, -parmest- calculates confidence intervals and
P-values from e(b), e(V) and e(df_r), as before.
I would like to thank Dan Blanchette of the University of North Carolina
for informing me about the bug and for helping me towards a solution, and
Jeff Pitblado of Stata Corporation for explaining to us (via Statalist) the
exceptional behaviour of -svymean-, -svyratio- and -svytotal- when the
-available- option is specified, and for reassuring me that no other Stata
command behaves in this way.
Best wishes
Roger Newson
--
Roger Newson
Lecturer in Medical Statistics
Department of Public Health Sciences
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]
Opinions expressed are those of the author, not the institution.
