Re: st: Tracking & documenting Change

[Nick Cox <njcoxstata@gmail.com>]

There seems here an indication that -Ins- changes Year to Year, but in
that case why the duplicates? Note that the duplicates get in the way
of counting transitions.

But I have to take your example literally because you really don't
explain the precise rules.

Also, I assume -Ins- is string because you don't specify and it makes
the code easier. But if not, then use -decode- first and use the
result of that, not the numeric variable with labels.

gen Status = ""
sort ID Year
by ID: replace Status = "Stayed" if Year > Year[_n-1] & Ins == Ins[_n-1]
by ID: replace Status = "Changed" if Year > Year[_n-1] & Ins != Ins[_n-1]
by ID: replace Status = Status + " " +  Ins  + " " +  Ins[_n-1] if
!missing(Status)
by ID: replace Status = Status[_n-1] if missing(Status)

Code not tested.

Nick

On Thu, Apr 5, 2012 at 7:05 PM, Rituparna Basu <basur@pamfri.org> wrote:

> I would like to track the change of insurance status of a person from year to year. After tracking, I would like to document them as  %'stayed-same' , %'changed from A-B', etc.
> Here is the sample data:
> ID    Year  Insurance Status
> 1        04       A
> 1        04       A
> 1        04       A
> 1        04       A
> 1        05      B             Changed A-B
> 1        05       B           Changed A-B
> 1        05       B           Changed A-B
> 1        06      B            Stayed B
> 1        06       B            Stayed B
> 1        06       B            Stayed B
> 2        04       A
> 2        04       A
> 2        04       A
> 2        05       A         Stayed A
> 2        05       A        Stayed A
> 2       05       A         Stayed A
> 2        05       A        Stayed A
>
>

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