Re: st: Problems with expand og reverting to original dataset

[Nick Cox <njcoxstata@gmail.com>]

There's also pertinent material within

SJ-8-4  dm0043  . Tip 71: The problem of split identity, or how to group dyads
        . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  N. J. Cox
        Q4/08   SJ 8(4):588--591                                 (no commands)
        tip on how to handle dyadic identifiers

Nick

On Thu, Jan 20, 2011 at 5:30 PM, Nick Cox <njcoxstata@gmail.com> wrote:
> Grethe:
>
> I can't see that the code I gave you would produce that error message.
> Somewhere in what you typed there is a period or stop . which should
> not be included, or so I guess.
>
> Ada's "correction" of my code is incorrect. I meant what I said.
>
> Nick
>
>
> On Thu, Jan 20, 2011 at 2:12 PM, Grethe Søndergaard
> <dkstatstata@gmail.com> wrote:
>> Thank you for your answers
>>
>> @ Nick Cox: I have tried to run bysort mother_id father_id
>> (birth_date) : gen diff = birth_date[2] -birth_date[1]. However, an
>> error message appear: "factor variables and time-series operators not
>> allowed". Can I solve this problem - by somehow changing the type of
>> variable that birth_date is?
>>
>> @ Ada Ma: My dataset consists of more than two siblings per family
>> (one line for each person). I am not sure how to find out which
>> siblings to be included in the dataset, if more than two siblings are
>> being compared. E.g. a family consists of children age 1, 4, and 8 (so
>> who should stay in the dataset). So that is why I choose only to
>> include persons with one siblings.
>>
>

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