Fred Wolfe <[email protected]> has a user written command that
uses the -bootstrap- prefix on another user written command:
> I have written a program to calculate differences between categories using
> bootstrap.
>
> . ndbdifference sex ,by(ra) seed(1) reps(25)
> (output omitted)
>
> The program works as directed.
>
> The code is:
>
> program define ndbdifference
> version 9.0
> syntax varlist [if] [in] ,by(varname) [seed(real -1) Reverse reps(real
> 100)]
> marksample touse, novarlist
> if "`seed'" != "-1" {
> set seed `seed'
> }
> foreach var of varlist `varlist' {
> preserve
> qui keep if `touse'
> keep `var' `by'
> qui keep if !mi(`var',`by')
> bootstrap `"`var'_b"'=r(dif), ///
> reps(`reps') nowarn nodots nolegend title(Difference between `by'
> categories) ///
> : difference `var',by(`by') `reverse'
> restore
> }
>
> end
>
> (omitted the rest)
Fred then points out that he changed the line
bootstrap `"`var'_b"'=r(dif), ///
to
bootstrap `var'_b=r(dif), ///
which conforms to the grammar for expression lists that -bootstrap- accepts;
see -help exp_list-. Those quote marks can confuse the expression list
parser.
Unfortunately, that didn't entirely solve Fred's problem because he got
the following error message when he added the -bca- option to -bootstrap-
name sex_b already specified
This error message resulted after -jackknife- finished estimating the
acceleration.
Fred found a bug in -bootstrap-. The bug fix will be available in the next
ado-file update.
--Jeff
[email protected]
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