Notice: On April 23, 2014, Statalist moved from an email list to a forum, based at statalist.org.
From | Nick Cox <njcoxstata@gmail.com> |
To | "statalist@hsphsun2.harvard.edu" <statalist@hsphsun2.harvard.edu> |
Subject | Re: st: bootstrap weighted mean |
Date | Wed, 2 Oct 2013 09:27:11 +0100 |
The third argument you pass to -myratio- is in practice weight, with comma included which may well be causing the syntax error. Positional arguments `1' `2' etc. are identified by Stata using two rules, spaces separate, but double quotation marks unite. A minimal test of this is to type weight , It probably doesn't matter, but it's better style to use scalars rather than locals to handle results like yours. Also, it's better style to pass weights to programs as such, not as extra variables, as Joseph shows. That's more flexible too. Nick njcoxstata@gmail.com On 2 October 2013 03:40, Shuaizhang Feng <shuaizhang.feng@gmail.com> wrote: > Dear list: > > I was trying to bootstrap standard errors for the mean of two > variables. When I do so for simple means, i use the following ado > file. > > program myratio, rclass > summarize `1' > local a1 = r(mean) > summarize `2' > local a2 = r(mean) > return scalar ratio = `a1'/`a2' > end > > and then do the following: > > .bootstrap r(ratio), reps(100) saving(cratio, replace): myratio u1 u2, detail > > and this gives the results as expected. > > however, when i wanted to do ratio of weighted means, i modified the > ado file as follows: > > program myratio_w, rclass > summarize `1'[iw=`3'] > local a1 = r(mean) > summarize `2'[iw=`3'] > local a2 = r(mean) > return scalar ratio = `a1'/`a2' > end > > > and then use: > > bootstrap r(ratio), reps(100) saving(cratio, replace): myratio_w u1 u2 > weight, detail > > then stata does not work properly and gives me the following message: > > invalid syntax > an error occurred when bootstrap executed myratio_w > r(198); > > > I am wondering if anyone from the list can help me out. the difference > between the two ado files seem small Thanks in advance. > > SZ > * > * For searches and help try: > * http://www.stata.com/help.cgi?search > * http://www.stata.com/support/faqs/resources/statalist-faq/ > * http://www.ats.ucla.edu/stat/stata/ * * For searches and help try: * http://www.stata.com/help.cgi?search * http://www.stata.com/support/faqs/resources/statalist-faq/ * http://www.ats.ucla.edu/stat/stata/