RE: st: RE: How to construct a duration variable?

["Scott Merryman" <smerryman@kc.rr.com>]

Here is one way.  It makes use of Nick Cox and Richard Goldstein's -spell-.

clear
input hhid    period  str1 brand    switch  Duration
1         1         A           0           1
1         2         B           1           4
1         3         B           0           4
1         4         B           0           4
1         5         B           0           4
1         6         C           1           2
1         7         C           0           2
1         8         A           1           1
1         9         B           1           4
1        10         B           0           4
1        11         B           0           4
1        12         B           0           4
1        13         C           1           2
1        14         C           0           2
end

tsset hhid per
spell b
bysort hhid _spell: replace _seq = _seq[_N]
rename _seq duration
drop _* 
l


Scott



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